If I buy copper membership can I wear sign and avatar without being full member or above?
I suppose you are planning to promote your new gambling website, so one way you can do that is by creating signature campaign in forum and hire other members to wear avatar and signature.
If you are active enough writing posts in forum and receiving merits you will rank up soon, and other way of promoting in forum is to participate in auctions made by theymos and advertise your business:
https://bitcointalk.org/index.php?topic=5393608.0