The easiest way to post pictures is to first join a photo hosting site.
I use photobucket.com. You can join it for free, and you won't have to worry about the size restrictions here. Once you have your picture posted there, all you need is the URL address of the picture. To find the URL of an image, right-click on it. Then click on "properties". A box will pop up, and about halfway down it will show the URL address. You can just highlight it, right-click on it, and click "copy". Then, when you post, check "embed picture in post", at the bottom of the screen you' re posting in, and paste the URL in between . The image you chose should show then when you hit "preview". If it does, hit "OK" .
If you want to post more than one picture in your post, just copy down the URLs of each picture and type each one in between , separately, and they should all show up.
example:





That would cause all three pictures to show up in your post.