I've seen lots...And I mean lots of people how to post pictures on the forum, Almost every single new forumer has troubles posting a picture. Don't worry, Slenderman is here to help
Step 1. Copy this address http://tinypic.com/
Step 2. Click browse
Step 3. Find the image in the file you saved it
Step 4. After done answering stop spam question, Click/Touch, "View full image"
Step 5. Your image will come up bigger, Click on it.
Step 6. Click View Raw Image
Step 7. Copy link in address bar
Step 8. Use in your topic to show image. (Paste the link between [img]and[/img]
I hoped this helped!