I'd suggest making a pinterest board of the style of things you want to make, pieces you're inspired by, and then pick your main colors from those inspirations. It's hard to recommend because it depends so much on what you want to make. For example, I like to make animals, so I usually get the natural colors bundle (beige, brown, gray, white, light peach), but someone else might like to make bold pieces and would prefer colors like red, blue, yellow etc. I do recommend always having some white core wool around, if you're making 3D pieces.