Go to photobucket.com Create an account.
click add pictures. You then find the pics on your computer, photobucket then will transfer the photo's from your computer to their website.
Then you need to highlite all of the URL
Create your thread then just under the box that you type in Instant UBB Code is a link called image.
Click the link and a box will pop up then paste the URL in the box, click OK.
You cannot post a picture from your computer. Needs to be in a online hosting site.