(Mods, sorry if this is already described somewhere. I'm writing this for someone and I couldn't find the instructions. Feel free to move this or edit it. )
If you want to add your own pic (such as a .jpg or .GIF) to a post, here's how.
1. Find the Reply button, and click it. Inside the posting box, click the Options tab.
2. You should now see the words File attachment. Under that is Add/Update. Click this.
3. Now visible will be a dropdown Upload File box.The default should show a dot in the Upload File circle, keep this dot if uploading a pic from your computer.
4. Browse for a pic in your folders. Click to gray the pic file name (for example, Picture123.jpg) Note: Maximum file size allowed is 350 kb.
5. Click the Open tab on the Folder box.
6. You should now see the File directory to your pic (something like C:\Documents...) in the Browse slot.
7. Click Save below on the Upload File Box. After that goes away, you should now see the pic file name (Picture123.jpg) under the words File attachment.
8. NOTE: Don't press the Add/Update again, that's what you already did. Only press later if you want to remove or replace the first pic if editing your post.
9. Scroll down in the large posting box past all the smileys.
10. Below the posting box, click Post. Your pic should now be visible when you view your post.