Not a rule but I'm putting this here. Here is a quick tutorial on how to add an image to your post.
First go to a image hosting site. For this example I used Tinypic.com
because they have tons of server space and they don't remove images for exceeding bandwidth or being NSFW.
When you first go to Tinypic you will be greeted with this screen:
This screen is where you will upload the pic you want to post on the forum. The first thing to do is click on the browse button there and navigate to the picture you want to upload from your computer. Always leave the file type as image.
*if your image is bigger than 640x480 please also use the resize drop down box there to reduce the size to 640x480 or lower.*
Once you have browsed to the file and selected it, click the Upload Now button.
The screen will think for a minute and you will be greeted with this screen:
All you need to do is highligh the code box I have poorly circled and then copy/paste the code into your post.