Get the skills that have a high ban rate first. I'd hate to have 99 fletch, fm, and cook then get banned on hunter. So i'd say Hunter would be a good start. Plus if i remember correctly you should have around a 30m profit by the time your 99.
Wc is good, decent money making one, can do ivys for fast xp and money, botted yews 24/7 no ban, got green h'ween mask (back then it used to cost round 15M)
Woodcutting is a nice one. Cheap as the only money you need is that spent on hatchets and its a fast skill to train especially once you get to Ivys. It's also an AFKable skill so you can do homework, watch TV, etc. while training. Bird Nest loots can also give you some good cash that you can use to train other skills