You have to first take a screen shot:
- Hit the Print Screen key on your keyboard
- Open Paint (or another image editor of your choice)
- Click edit, then click Paste
- Make whatever changes you want/need to make...save it
Then upload it to a host...there are several that are free. I use PhotoBucket, but there are several other good ones.
Then, just as stated above, type out (img) put your link here (/img) ... but you have to use [ and ] in place of ( and ).
There is a little yellow icon you can click that just sets that up for you in the posting tool bar...it looks like a couple mountains or triangles with a little sun above them, or a circle...like so...
Enjoy!