What I do is..
Go to
www.tinypic.com and sign up for a free account.
Once I am signed in there is an upload button. Click that.
Just find the picture you want to upload and select it.
You are also given the option to resize the picture if you want.
Finally once it is uploaded it spits out a link for you to copy and paste. It will start with IMG.
Then write your post here, and paste the link and you are done!
If you run into a problem send me a pm.