When you don't have the luxury of lots of space, the first thing you have to do is strategize how you'll make everything work well together. One foolproof way to start is by using a monochromatic palette. It will make the space look larger and will work with, rather than against, the other elements in your design. Choose the same or similar shades for the walls, carpets and drapes. This doesn't have to be a compromise move, even if you love vivid color. Just indulge yourself in your choice of accessories, wall art and textiles.
If this sounds bland, there are hidden benefits you may not have considered. If your studio apartment has odd angles or other irregularities that you want to camouflage, they'll tend to blend into the background when you keep it neutral. A neutral palette will also make it easier to perform seasonal wizardry, like switching out a cherry red area rug for a pastel green option in spring.