For me, the most important thing was buying binders first, since wearing three baggy sweaters in the middle of summer isn't exactly the healthiest idea, but I was determined to hide my chest. It didn't matter if I was dying of heat, I refused to take them off out of fear of my chest being exposed. :/ So yeah, binders were definitely the first thing on the list to buy.
Next came buying men's clothing. It's a bit hard to find something that fits well though since I'm tiny (yay. 5'0 -_-), but I do find that mens pants fit me much better than women's pants! :X Or maybe it's just my imagination, but damn do I ever feel a difference. When I wear the remaining girl clothes I have, which are fairly androgynous looking, it just doesn't feel right on me. They cling to my curves, and it's just blehh. I am slowly working on replacing my wardrobe with all male clothing. >.> Now if only I had the courage to wear the pair of boxers I bought, ahaha.
Now, the next thing on my list would be an STP, but that would be really awkward showing up on my mom's paypal account...so I'm waiting until I can order stuff myself and yeah. This sounds stupid, but I dread peeing because I get so mad because I can't stand up and pee. O__o; Like, I dread it so much that I purposely avoid it until my bladder hurts. It's definitely not healthy.
Therapy, well, my parents are currently paying for my therapy since I've been in it for non-gender related issues since I was 10 or 11, and obviously a 10 or an 11 year old can't pay for their on therapy. But we often explore my gender in therapy so...yeah. When I go to college, I plan to also start seeing a therapist who specializes in gender stuff, but more than likely I will have to pay for that myself.