Perfecto. You can also hit the quote button, then paste, then hit quote again. The one with the / in it has to be the closing one, though.
Probably the way you just did it is better, but I started with what I just wrote, and it's now a habit.
For drill three:
Once your photos are on a photo hosting site (such as Imgur.com; Postimage; Dropbox, etc.
Photobucket),
or on virtually any site, (including this site's album) such as eBay, Amazon, you-name-it, select the full sized image, then Control-click (Mac) or Right-click (Windows) on the image itself, then choose "copy image location" or similar words. Now paste that URL (the full web address, which should end in .jpg or .png) into the IMG box in the reply window of the thread you're posting to.
The site's album is also a good choice for displaying photos, and the same method works for obtaining the image's URL for copying into the IMG box.