How it works on your
blog depends on which blog site you're using...
To post images on the LATOC Forum, go to your hosting site and bring up the image you want to use, then right-click on that image and select "Copy Image Location" from the pop-up menu. Then, in the body of your Forum posting you can type {img} then hit ctrl-v to paste-in the image URL, then type {/img}
But you have to use the UNSHIFTED, square brackets instead of the sideways mustache brackets I used. (If I'd used the correct ones here, the Forum software might've tried to read a non-existent image.)
You can also just click the "insert image" button that appears on the compose message page, then paste your image URL in-between the "img" tags that will be inserted into your text. Or paste your image URL, select it, then click the "insert image" button to have the tags put where they belong.

Hit the "quote" button at the top of this message and you'll be able to see the code I used to insert the "Simple Machines" logo above.