like how and what exactly should i do (exact steps) so that i have a succesful sell

Do you mean creating screens?
Give me more details on what your trying to accomplish.

i am trying to be able to put my screenshots on here so people can see them that way the know what they are buying like your doing with your set

ok, what kind of file do you have?
Assuming its a .tga

Navigate to your toribash folder(where you installed toribash)
Find the folder called "custom"
Head textures right?For this to work, the head texture file MUST be named "head" And be a file type of .tga
Now, create a folder inside the "custom" folder(it doesnt matter what its called)For an example lets say you used "preview"
Put the "head.tga in there
Now go in game. Type /lp 0 preview (or whatever you used)
Now take a screenshot (F8 I think).
Almost forgot: you must have an tem.ini file that says you have the texture item so go to any folder thats there that you know has it(just use the .ini files inside hampas folder)

k and then how do i put it in art/textures? like how to i get it online

Well first, did you make screenshots?

yes i have the screen shots

well first, you have to upload your image to an image hosting website(dont ask me how, never done it)

da** k sadly none of them are letting me upload right now..

Try imgur.com It is reliable and fast
Once you do that, you click on the

icon and you put your image link in there