The steps you should follow:
1. Go to the System Information page and create your character's "Self." As in, their stats, model, and aspect.
2. You have 2,750 Z(enny) to start with, purchase weapons and other equipment with it.
3. Then go to the Special Weapons page and choose up to 2 Special Weapons (1 at the minimum, but only 1 if your Data stat will not allow 2). These Special Weapons must be one of the first two listed in thier respective coloums. (Ex: Repair Function 1 or 2)
4. Go to the Techs page and choose 1 tech.
5. If you have designed any of your own techs or Special Weapons, go to the Gaurdian page and decide if you want to become the Gaurdian of any of those that you created.
6. Post all this on the Message Board in the "Joining" section along with a semi-in depth history and a brief personality description (in accordance with the history summary applying to your aspect... Oh, and try to keep it PG, PG-13 at worst... Attach warnings to anything that isn't).
7. Enjoy, but know that if one of your techs/special weapons is too powerful, you'll have to make a new one or choose a different one.