Build your classes and class names. Anything you leave on "Keep" stays exactly as it is on your account. When you're done, press Generate Code, copy it, and send the code to your ticket in KiiLz Services.
Classes 6–10 are saved to your account now, but the game only shows them once you prestige: class 6 at Prestige 1, class 7 at P3, class 8 at P5, class 9 at P7 and class 10 at Prestige 9.
Pick a class, set what you want. Any gun and any perk can go in any slot. Attachments only list what that gun can take.
Up to 15 characters, color codes count. Leave a box empty to keep that name.
Copy all of it and send it to your ticket in KiiLz Services.