What I find easiest for me it to upload the pictures to photobucket or a similar version of it and then copy and past the image url to my posts. Hope it helps! ETA:
and from PA! To post a picture, click on "Uploads" at the top of page header and Browse for the picture you want. Size it to the correct size. When you want to include it in a post, start your post, click on "uploads" and at the bottom of the page on right you will see "my uploads". Then select the picture you want and be sure to have the correct size. Good luck!