It's hard to tell from the photos because I can't see part of the room where you are standing when you took this photo. But I'd say put the bed headboard directly opposite to the closet.

Can you show us the other side of the room? Or give us the full layout?

Without a floor plan or pictures of the rest of the room, it's hard to give suggestions. But I'll try!

I like that the kitchen is not smack dab in the middle of the room. That helps a lot. Try separate the room into sections--a sleeping area, a sitting area, maybe a work area and an eating area. You can define the areas by using rugs, or the placement of furniture, or color. You can also use curtains or bookcases, but in a really small space, I think that sort of thing tends to make the room feel even smaller.

Do you have a TV? That's going to mean that you need wall space for the TV, and seating at a comfortable angle/distance from it. Do you want your bed near the window? or closer to the door for darkness in the morning? Do you need a table for eating/using the computer/crafting/homework?

This looks like a small space, so I'd rethink the dresser. Maybe get a nightstand with drawers instead, and rework the interior of the closet to hold all the rest of your clothes. Then you could fit your bed along the wall opposite the closet, and a chair and TV between the closet and the bed.

One possible scenario for your space arrangement:
Bed: place on the right side of the photo, so that it is perpendicular to the room and the nightstand is adjacent to the closet.
Dresser: if you have not invested in a dresser yet, I suggest you get an open bookshelf like this http://m.ikea.com/us/en/catalog/products/art/80071357/. These tend to be not as deep as dressers, but you can still store your clothes/shoes if you fill it in with boxes. That way you can have all your clothes on bottom and books, jewelry, etc on top shelfs. It can even house a TV.
Small seating: Chair and small coffee table can be placed by the window (opposite the closet?) so you will get natural light for reading, etc. Positioning the chair on an angle to the window will prevent glare on electronics.
Decor: Hang art/pictures above the bed for a more complete look. Or consider covering the wall with an interesting wallpaper.
Here's a sketch I did for your space: http://m1342.photobucket.com/albumview/albums/CollageInteriors/D935C8AA-7865-42F2-B1FA-89CEB0464B4B-6757-000003F7043F3A56_zps10e2155d.jpg.html?o=0
CollageInteriors@gmail.com