I'm bad at explaining, and someone will probably post an answer before I finish, but I'll try...
At the top of the page youll see the word "upload" Click it, a new window should open. Click browse and select a picture from your computer. Then after it goes to the upload completed page, click the back button, back to the upload page, at the bottom of that page will be "my uploads" lower right, click it and you will see your uploaded pics in a new window. Highlight the linky words in the lower box below the picture for posting on forums, right click, pick the word copy (oh, when you upload, change the sizing to 'for webapages and forums) Minimize the picture page, go to where ever you want to post, start your reply, then when you want the pic, just right click and paste.
I hope it works for you, I'm really terrible at directions! Someone very kind here on BYC helped me out and held my hand through it, but I have a feeling I didnt do as good a job! I really hope this helps, if not, you got a bump and maybe someone else can be more specific.