Open a Google+ account. Much easier. If you install Google Drive, etc., you can automagically sync photos from designated folders (to protect private stuff).

After that, just right click on a photo in your computer's folders, via Windows Explorer or other, click on the prompt to upload to Google photos, then embed the image URL to the forum.

Much quicker and easier than Photobucket, Flickr, etc. I haven't used any of my other photo hosting accounts in years. Photobucket was always a sluggish kludge anyway. And Flickr made itself less usable after Yahoo disabled easy interfacing with Facebook, etc. Google integrates this stuff much more seamlessly, although I'm not thrilled with their decision to phase out Picasa.