The best place to start when doing your first breeding project is right here. Xavion lays out everything you could possibly want to know about breeding to 6 visible (or less).

Well, you have two basic choices on how to start:
1) Essences - if you are really picky about the colors (or have really light/dark colors) you'll pretty much need advanced otherwise you'll end up having to use dyes. Regular essences have pretty bad color swings and I really only use them for traits that are hard to find. Cost of essences can vary greatly depending on species.

2) Use public breeding/buy cheap pets with desired traits and then dye the final pair. This can be a cheaper method, but depends on the cost of essences and how many color slots you'll need to dye. Again, regular dyes can have pretty bad color swings, but you can get them from the scale shop so having to use more than one isn't quite as bad.

Definitely read the guide mentioned in the previous post and have fun!