Okay, this is pretty easy!
You need to code it yourself to get it to work, at least that's how I do it.
First you copy and paste the link into the post window
/forums/
Then you add the codes on either end and add the descriptive text you want. I've included spaces so you can see what I'm doing. You can only have spaces in the descriptive text area only, otherwise you break the code.
[ url = /forums/ ]FineScale Forums[ /url ] only remove any spaces, and you get:
FineScale Forums
Remember there can't be any spaces between the square brackets ([ ])