Board Thread:General Discussion/@comment-11766202-20130923204157/@comment-5064773-20130929054551

In the infobox, put the image name after "|image=". For example, "|image=Mistress Therana.png".

If you want to just put an image off to the side (outside of an infobox), use " ". Adding "|thumb" right before the last two brackets will make it a thumbnail, and will let you add a caption by adding "|inserttexthere" after the "|thumb".

Obviously, don't add the quotation marks. This should work if you're using source mode to edit, and not the visual editor. You can look in "My preferences" if you're unsure what you're using.