1. Go to www.imageshack.us
and sign up for an account.
2. Login to imageshack.
3. Click the "Browse" button and locate the file on your pc.
4. Click "Upload".
5. When the page loads, click the "links to picture" so it will drop down.
6. Locate the "direct link to picture" url and copy/cut it.
7. Come back to your post.
8. Click the "IMG" button, it will put two image codes up and leave the cursor bar between them.
9. Control+v to paste the picture's url.
10. That's it.
Should look like this: