Under the screen you get when you make a post, or post an aswer, you will see, on the left, “Attatchments” and then over to the right a blank space, with “browse” next to it. Browse to where your image is held, making sure that it is is no more than 800x800 pixels in size, and attach it.
You can attach up to 5 images to one post using this by posting the first and then edtitng your post to add the 2nd, etc.
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