ok, first take your picture with a digital camera, or webcam or whatever you use
and then upload it to your computer
then go to
http://imageshack.us/ and click the browse button.
then find that same picture that you just uploaded to your computer through the browser that it brings up
select it and click ok
then just below that, click "Start upload!"
then when its done, copy the forum link(if your pasting on these forums, which i assume) and paste it into your topic
if you need me to explain anything better just ask
edit- turns out theres a simpler way for these forums.
instead of using imageshack, just scroll down to the bottom of the page on here, and click the upload attatchment button, then click browse, find it through the browser and attatch it to your post.
either way works though
for example
[attachment=0:39n157ax]Harriet%20Tubman[1].jpg[/attachment:39n157ax]