I place a copy of my photos on to Imgur (any other free photo/file sharing platform will do).

Then I place a direct link to the photo on to this forum.

Just be aware that the forum has already added a http:// doohicky so that you have to remove that first or you will get a double when you paste the link (like this...http://http://, or you may get http://https://), and those won't work.

Red arrow points to the 'extra' http:// that you remove if your link already has that in it.

Imgur is a https:// site and when you find your image on Imgur and select it you get a choice of what to do. Choose 'Direct Link' and click on the 'Copy' button beside it. That will give a https:// 'signature' plus the Imgur number of your photo.

All you are seeing with my photos on screen is my photo directly linked to your screen from Imgur.

Easy as. Do a couple and try it. 

On the forum doohicky, once you place the link in that box where the red arrow is you have to choose 'Preview' first before you can click on 'OK'.