I'm going to try and see if I can make this easy... sometimes my brain gets ahead of me, so please bare with me!
Fist start a post, then click on attachments and other options (the plus sign beside it) It's right below the box you type in.
Go to Attach and hit choose file. Now you will need to know where the picture is at that you want to upload. Choose file will open up a box for you to select that photo. If you need to post more than one picture, click on the more attachments that is right below the Choose File button.
I'm going to try to take some screenshots and make this more of a picture tutorial too! Been a long weekend and work is interfering (right now) with spending more time on doing it better.
Try this out and let me know how it works. I do think this is easier than any of the online image sites out there right now!