Can you paint the cabinetry? I would paint that white if I could then do a fun color on the wall... or even a neat pattern that simulated wall paper

add a large white rug and textured white shower curtain.

then add a large colorful object wall art over the toilet and accessorize the sink area with coordinating colors (I am going to suggest orange or yellow with turquoise).

temporarily replace the knobs on the cabinet with white ones or colorful ones to match your accent color (just spray paint other knobs and replace the old ones when you move out)

spray paint a large frame either white or a bright color and hang it over your existing mirror... like this:

http://nestingplacenc.blogspot.com/search?q=bathroom mirror

Since you probably can't do a major overhaul on the paint and tile you should change a few things that you can control like adding accessories.

First, change the fluorescent bulb to something brighter. A high wattage CFL would do nicely.A plug-in night light could also add light/atmosphere (sometimes there's an outlet on the opposite wall). Otherwise, if that's not enough, go to Home Depot or Lowes and invest in a whole new light fixture.

With bathrooms that small, I would suggest a clear shower curtain to open up the space and to give you more light while showering. But if you must go solid, do white, yellow or silvery. (They have some great "clear" options that aren't see-through).

Normally I would say NO to bath rugs, but a bright white rug might hide that gritty tile floor (just not one that rings that toilet).

And if all else fails, candles.

I think this aqua and apricot combo would be a nice way to brighten up the space.... http://www.thekitchn.com/thekitchn/kitchen-color-inspiration-apricot-and-aqua-089211

Since the counter is beige and the tiles are another color or tan and light brownish I would paint the cabinet and walls a bright white semi gloss. I don't see colors it would compete with the two tone tiles and light beige counter too much going on for a small bathroom then it becomes choppy. If you want to freshen it up and making it brighter white would be the way to go. You can add an accent color by changing out the cabinet hardware maybe a turquoise or orangey poppy knob- Anthropologie would do the trick-

If your budget allows maybe changing out the faucets in a brushed nickel o something simple and timeless would really help.

maybe hang white shelves above the toilet to stack some white towels and some bath products to tie in with the cabinet hardware. This will give you some storage and get a nice white woven bin to store misc. things in and keep the shelves looking neat.

Rugs in bathrooms never work for me its becomes something I have to wash every other day.

http://www.anthropologie.com/anthro/catalog/productdetail.jsp?_dyncharset=ISO-8859-1&_dynSessConf=-9095458668265466102&id=873084&parentid=DECOR_HARDWARE_KNOBS_HANDLES&pushId=DECOR_HARDWARE&prepushId=DECOR_HARDWARE_KNOBS_HANDLES&popId=DECORATING&sortProperties=&navCount=14&navAction=poppushpush&fromCategoryPage=true&selectedProductSize=&selectedProductSize1=&color=tel&colorName=TEAL

Same problem over here- if you can, paint the cabinets white and get some nice new door handles in a bright color or cool design.
As for the walls, I wouldn't go with anything other than white since it's so small, but punch it up with great accents like aqua or red.

Finally, if you can, lose the ugly faucet handle!

The OP doesn't state if they own or rent -

If she owns, changing out that countertop/sink & medicine cabinet and painting that vanity/sink is not a costly expenditure.

As far as paint colors, with all that sandy beige I'd suggest something in blue (visualize ocean and beach) or pink (think of the inside of a seashell)

I'd stay away from greens or yellows as they can make you appear sallow - not what you want when applying makeup.

Finally, stick to plush all white towels and terry-cloth bathmats (not the looped kind with the latex backing)

Bright yellow accessories and soft gray walls

i, too, like lots of white with pops of color. if you can paint the cabinets, how about white or a muted aqua, which would be a nice accent to compliment that counter color.

Add a white textured terry shower curtain.

how about tile stickers, especially for that brown vertical strip? there are some attractive retro ones here: http://www.2jane.com/tile-stickers-tattoos.aspx

and as long as you've got that 'crystal' knob on your sink, match it with crystal cabinet knobs.

as for over the toilet, how about something 3-D. like this: http://www.etsy.com/view_listing.php?listing_id=27516782

or a wall graphic: http://www.etsy.com/view_listing.php?listing_id=25082045

good luck! this is a fun challenge!

Bepsy, the OP does indeed say they are renting, in the first line.

*bepsf

I had a bathroom with similar colours in my last apartment which I painted a sunny yellow. It definitely brightened the room and made it loads more cheerful, but I have to agree with bepsf -- it's really not ideal for applying makeup.

Definitely paint the cabinet white if you can. Ask your landlord, you might be surprised at the answer. I'd opt for a pale ocean blue-green for the walls (think tropical beach!)

I wish people would read the actual post before commenting. "Alexandra send [sic] in an email. She writes: I am renting an apartment starting in August"

If she rents, I highly doubt she'll be able to paint the cabinets or replace hardware (unless she gets permission from her landlord). I think Littleloveables' suggestions are the most workable in this situation. Use white wherever you can, minimize clutter, keep things simple (plain swathes of color rather than fussy patterns), add art and perhaps a plant.

Pale ice blue walls would brighten things up...

I like the combination of wood and terracotta so I think (unless the photograph is deceiving) that it's already very pretty. I'd go with the pale pink walls suggested above. You could have accents of pure primary colors in some artwork on the walls and/or their frames. This would convey a natural look, in my opinion. Definitely upgrade the lighting, if necessary.

an over the potty shelf - and have rolls of colorful bath towles and baskets for bath needs - a hand mirror - hair care etc.

http://www.homedecorators.com/P/Mission-Style_28W_Spacesaver/820/

a wonderful shower curtain can make a big splash here are some great ones.
http://www.urbanoutfitters.com/urban/catalog/category.jsp?popId=APARTMENT&navAction=poppushpush&isSortBy=true&navCount=3&pushId=APARTMENT_FURNISH&id=A_FURN_BATH

a fun rug would be nice I like the ones that look like manhole covers.
I think black and white would look good you already have pink tile and can not change that- a very light grey on the wall wall will blend with any touch of color you might add.

http://www.prankplace.com/manhole.htm

A nice shower curtain would help a lot! I also really liked the suggestion of adding a frame around that mirror!

Not allowed to paint? Try a bright, funky shower curtain in a fun design or a really saturated, sheer colour. Get a coloured vase and put in big, fresh flowers. You could also try hanging some art behind the toilet. Maybe a framed vintage movie poster or a scene from a fun vacation you went on? Just work with accessories and other little things you can change. The bonus of this is that you can change it around and mix/match to your hearts content whenever you get sick of the current layout. Hope that's helpful :)

a pale gray wall will compliment many colors like your pink tile. I think black and white urban modern showercurtain- and a rug that looks like a manhole cover - and an over the potty- shelf in straight lines to hold your rolled bath and hand towels and some baskets for bath products and scented soaps in a crystal dish.

a gorgeous DARK brown on the wall, it'll make the drabbish pinks and beiges and off-somethings pop, then add some brilliant white objects to DAZZLE

No one will notice if you give it another coat of the best white paint you can afford and then, marimekko shower curtain, towels and carpets. Some bright cheery artwork and it'll be just great!

is it pink? Or peach? I thought it was pink, but some of the comments are saying peach. If it's pink, I like aqua/turquoise! I love the S. Beachy-Art Deco combination of pink & turquoise/aqua, especially with a nice, bright white to offset.

put a colorful picture over the toilet, get some nice towels / bath mat to pick up the color and change the knobs. End of story!

my bad

I agree with changing doorknobs (these would go with the faucet: http://www.anthropologie.com/anthro/catalog/productdetail.jsp?_dyncharset=ISO-8859-1&_dynSessConf=7037022991794743711&id=870102&parentid=DECOR_HARDWARE_KNOBS_HANDLES&pushId=DECOR_HARDWARE&prepushId=DECOR_HARDWARE_KNOBS_HANDLES&popId=DECORATING&sortProperties=&navCount=18&navAction=poppushpush&fromCategoryPage=true&selectedProductSize=&selectedProductSize1=&color=ame&colorName=AMETHYST)--keep the original ones for when you move out. My guess is your landlords will be glad for the free labor if you painted the cabinets (white) and the walls (light gray), with their permission of course. Then add this shower curtain: http://www.anthropologie.com/anthro/catalog/productdetail.jsp?_dyncharset=ISO-8859-1&_dynSessConf=7037022991794743711&id=990014&parentid=BATH_BATHROOM&pushId=BATH_BATHROOM&popId=BATH_BATHROOM&sortProperties=&navCount=11&navAction=&fromCategoryPage=true&selectedProductSize=&selectedProductSize1=&color=pin
Good luck!

"I wish people would read the actual post before commenting. "

I wish all comments were constructive and not berating of other commentators.

*shrugs* Oh well.

I've painted and changed things from places I've rented too. I think it's helpful to know what all your options are.

see - i like that shower curtain you linked in this bathroom alot! (assuming a gentle gardeny-flowery type fits in with your design sensibilities). good recommendation!