People will post on your thread about price (they want to lower price more). If a deal is made, he will send you tc and he will send the the FLAT TEXTURE FILE.
Flat texture file is the real file in which you drew the texture. You need to upload that file too.
Also, there is a chance that the person will scam you. Scamming is when a person do not give you the material he dealed for.
To make scam reports, make a thread explaining the situation in the "scam reports" section.