How to add a signature to forum posts.Having a problem with the post requirement

Basically i just replied in a ton of anime posts and some other places till i got 15 posts but it still says you need 15 posts to post links.I wanna set up a few anime gifs as a signature and would also like to post imgur links since im planning on selling my league of legends account cus i got burned out after playing it for so long.Any ideas?
Also i posted this here cus i dont know where to post this so sry about that ;-;

- - - Updated - - -

Wait nvm close the post sry for the inconvenience.The site just didnt process it immediately but now it doesnt show the 15 posts thing.
Sorry again! ;-;