Hi there buddy, I know that the forum's big and can be quite confusing. Here's a little help for you.
Go to Trade Plaza if you need to open a Trade Shop.
Though you must read the rules before creating your own shop.
If you have any enquiries about setting a Trade Shop and regarding the rules of the sub-forum, please contact the moderators in charge of Trade Corner, Mac, Tabor62
Hope that helps! Adieu! ;)