how do i make this puppy stick to my blog??

i have a rlly cute blog layout with a little gif of a dog barking, but i was wondering how i could get it to be at the bottom of my blog (almost as if my blog is a speech bubble and the dog is saying whats in it)

right now its just stuck at the bottom of the screen TmT

heres one of my blogs for reference!!

also.. if possible.. help me with a layout to actually add a speech bubble around my blog >⩊<