How to add custom registration field?

[Frog_vbulletin3_import11966]

like topic name says.. how to make custom registration field?like"how did you find us" etc, and how to make this mandatory?
any suggestion?

Thanks
Best Regards, FroG

 

[Fios]

Admin CP / User profile field manager / Add new profile field / . Select single line text box and click continue , than enter a title, description, and check the other options to how u want .