Try something like this:
[img]http://cvcl.mit.edu/hybrid/cat2.jpg[/img]
This would make:
Between the [img]http://and the[/img] is where you put the URL for your picture, which must be located somewhere on the internet.
If the picture is on your computer, try a place like
PhotoBucket. Just make an account, upload the picture, and there should be a link part that says forums or something, and starts with [IMG] . Just click on that and it copies the whole code, just paste it into a post and it should work.
