I'm to blame as much as anyone for a lack of visuals in this forum. I insert photographs, drawings, maps, graphs ... so infrequently that I usually forget how to do it. But it really is easy:
1. Know where the picture file that you want to post is on your computer.
2. Leave this box and scroll down to the Additional Options section. Click on Manage Attachments.
3. Browse for the file and upload it.
4. Come back to here, the Message box, and scroll down the Attachments list to the file that you want. This will insert an attach number here.
5. Go to Preview, where picture should be visible.
prevalenceEngland1_00_50_50_75_100_H500.jpg
6. Submit.
John