Basic white sheets are probably the best investment we've ever made. Change a pillow case or throw a different colored blanket along the bottom of the bed and voila, a whole new look for the bedroom. Another great way to augment plain white sheets is to stamp a pattern onto them using anything from a potato to piece of linoleum to a stamp you might already own. Using non toxic fabric paint, stamp a simple pattern along a border or go whole hog. Jump below for inspiration and a how-to from Todd Oldham.
A tutorial with Todd Oldham and Susan Sarandon on how to use plastic cups and fabric paint to create a modern circle pattern on your sheets. You can also check out the how to instructions in the book Todd came out with a while ago called Handmade Modern which is filled with great MCM inspired DIY ideas.
Make it Mine Magazine shows us how to make a potato stamp using a cookie cutter (for those of us less confident with our freehand abilities).
For regular potato stamping instructions, check out poopscape's tutorial on how to make the lemon slice pattern above. Or if you're not into making your own stamps, there are plenty of etsy crafters who can make them for you. Check out Bossom Stamps to start.
Readymade's potato stamp dress is a great jumping off point for a simple one color pattern.