I actually use paint shop pro myself, to select just the dragon (because it is all black on a white background) you could use the magic wand selection tool, click on the black dragon and it will make a selection, copy and paste it as a new image and it should put it on a transparent background then save it as a new name and copy it and place it as a new layer on your sig and move it where you like. It can be tricky to figure out the harder stuff and that is a pretty advanced thing to want to do really! You did a great job over all for sure SherG, for your first try!
Edit : another way you could do that (that would be easier) is fill in the white with the same blue background color you used it the sig with the fill tool, that would make it blend in like it was on a transparent background!