Try blending the image with the background more... signatures look alot better when it all blends together, if you know what I mean? D: 'Cause the images just stick out like a sore thumb. The backgrounds seem blurry... Not every background has to be put together using photoshop filters and random brushes, there's some pretty awesome textures you can find that are fun to experiment with. (link, link). The text is difficult to see also D: I recommend downloading some fonts over at dafont.com.
Nethertheless, not bad for someone who hasn't been using photoshop long. ^^