I've unbuilt and rebuilt a lot, the way of the mountain biker... The most important thing is to have the correct tools, and a buddy familiar with them to teach how they're used. Bike tools are weird, and highly specialized. No book is the same as doing it, and good on you for wanting to learn !
Putting in headsets and bottom brackets is the tricky bit 'cause the tools are so odd. A high end sealed headset is the toughest part, at least for me, so don't be afraid to bail if you get confused. It's all in the minor adjustments. If whoever is helping you is a good mechanic though, you're in for a real treat. We girls get to ask the dumb questions, don't pass up the chance to learn. A lot of a good bike build is in the hand of the mechanic- a master who does this all day and then rides, so if things aren't totally copacetic when you're finished don't be ashamed to have somebody fine tune it. ( And harrass them with questions if you can) You mess up once or twice along the way. As long as you don't force anything and break it, you should be fine.
You go girl. Bond with the bike.

missliz