How do I include an image in a forum post?

You have to have them hosted on another site, then point your forum post at the image on the other site. I use postimages.org (it's free), but there are others. Some of what follows is from memory, but close enough you'll be able to figure it out. Very easy to get set up with them (you'll need to create an account, as far as I know).

Upload your image(s) to your postimages.org account. Click on My Images on the upper right of that site. Hover over the uploaded image that you want to link to. One of the floating icons that appears over the image is for "sharing". Click on that icon, and you'll get a list of possible link addresses that you can copy into your forum post here. Use the link address for "Thumbnail for Forums". Click the copy icon to the right of that link address, and paste (ctrl-v) into your forum post, like so:

Voila! It'll take you a few minutes to set up the account on the other site, but once you've done it once, the whole process will seem trivial.

Click on Quote on the bottom right of this post to see the link address I copied here to bring up the thumbnail above. The entire line beginning with "[url=" came from postimages.org (the image itself is hosted on postimg.cc, which is what the url points to). Just copy and paste as I noted above.

Anyone who clicks on the icon will be taken to a full version of the image on postimg.cc. I'm sure some of the other link addresses might be useful too, but I haven't played with them.

Dirk