Ok 1st thing to do is go to one of those free picture hosting sites and make an account there.
I use
http://http//www.photobucket.com
when you upload your pic to that site (painless really just browse and click on the pic on your PC, & wait for it to upload) It will give you a box under it with a few links to copy and paste depending on the forums code (URL. HTML. IMG)
to make the pic in the post like this in your posts posts use the IMG code
Example
If you want to have a smaller pic that needs clicked on to view the larger image, then you'll need to use the new reply or new thread button to get to the regular posting area, this includes a box at the bottom to add attachments, you click on browse this will open a folder page of your PC for you to choose your picture from (assunming you have the pic or attachment on your PC) once you click on it the link appears below in the text box, click on add attachment and it will upload to the server here
to place in your post like shown below
Example
SFS1.jpg (Size: 5.27 KB / Downloads: 5)
you simply click on, insert into post
if you change your mind, click remove.
Hope this helps
Faith Divides Us, Death Unites Us.