Bootlegged from another site, but it works:
1) Enroll on a free photo hosting website to upload pictures to. Most people use photobucket since it is free and easy to use so my directions are based on them.
2) Once you have your Photobucket membership, upload photos to the site from your computer. Do this by clicking the "Browse" button near the center of your screen. This will bring up a window you use to find the pictures you want to upload. (Typically pictures are stored under C:\...\My Documents\My Pictures, but it could be different on each computer). Double-click on the image file that you want to upload. You will see the file address show up in the "Picture" dialog box beside the "Browse" button you just used. Now click "Submit" just below the dialog box. Your pictures will be sent to your photobucket account. It may take some time depending on the size of the image file. If you have more than one image to upload at a time, click the expand arrow (the little "down" arrowhead button) on the "Submit Multiple Pictures" dialog box and select the number of images you want to upload. Follow the same steps for each image as outlined above.
3) Now your images should appear near the bottom of the page. They will be thumbnails that you can double-click on to expand to full size if you want. Underneath each image there will be three dialogue boxes (A Url, a Tag, and an Img box) with text in them. For the purposes of posting a picture here you will only be concerned with the "Img" line. (The URL line can be used in your profile to submit a picture for your avatar, but I am not going to get into that here.)
4) Single click on the IMG text in the "Img" dialogue box. This should highlight the text. Copy this text (Either by using Ctrl+C or right clicking and selecting "Copy").
5) Paste what you have copied into your post here. It should show a [IMG] at the begining and the end of the line you pasted. Make sure that there is a space between your post text and the [IMG]'s (no spaces in the part you pasted, just between what you pasted and the text of your post).
6) Finish off your post and preview it. Make sure the photo is there and then submit your post. If the photo is not there, check your pasted link to make sure you didn't miss a bracket somewhere or inadvertently put a space in the line somewhere.
Here's proof:
