I'm a grad student on a very limited budget, and have recently re-focused my wardrobe around an autumn color palette. I'm not quite done, but here's how I recommend starting:
I've found it's easiest to keep to neutrals on the bottom. So in the early stages (as a winter) keep to black, gray, and maybe navy pants and skirts, and black and gray shoes. These aren't near your face, and should go with most of what you wear up top.
Focus on getting some colors up near your face. There are a couple different approaches to this, depending on how many layers you usually wear, and what you already have. 1) If your top/shirt is always showing, focus on buying those in winter colors. If you wear knits this should be pretty cheap, and not too difficult. 2) If you usually have a jacket/sweater over your base layer(s), focus on buying colorful jackets and sweaters. 3) If you already have a substantial collection of neutral clothing that you love, focus on some chunky necklaces and/or scarves in your colors. This gets color by your face, can be quite inexpensive, and allows you to continue using the clothes you already have and love. Any combo of options 1, 2, and 3 works, just be careful to have some neutrals up top so you don't overdo it.
After you feel good about your selection of colorful clothes for your upper half and/or accessories, then I would get some colorful shoes that work with most of your upper-half colors. An outfit of entirely neutrals with just some colorful jewelry and colorful shoes is far from dull and can compliment your skin tone.
Finally, it really helped me to be ruthless about sticking to my color palette. A lot of YLFers follow less strict color palettes, but for me it really helped to stay to a palette where I know that almost everything in my wardrobe matches. I hate having items that only match one or two other things I own.
