Floating Image, help?

I want to start customizing my den page but I need some help. I want to create and add a little image that sits or 'floats' in the bottom corners of the page and stay fixed while scrolling up or down the page, essentially staying over the background image. However, my experience with HTML is limited to like 2 years I played Neopets back in like 2006 so.... I could use a little help.

Anyone have a nifty guide that they could share?

Not sure if you still need it, but I'll post it in case someone else finds this thread while searching for an answer regardless~

In this thread, an amazing user has provided some free html goodies, including floating pagedolls! c: