well first of all its kinda too big, and its a square, sigs are usually rectangles like mine or like other people here.
And i also dont really like how you change the color, doesn't go with the image. And the names seems too out there.
Instead, you should just crop the image, and add effects into the background first. Use cd4's, brushes. Heres an example of what i mean.
i croped out the image, and i hardly use any brushes. Thats a good way to start to make siggies. And look at my siggie now, looks different then how i used to make sigs. And even i still have a lot to learn.
An example of a good fiesta siggie is here
http://www.fiestafan.com/forums/showthread.php?t=20552
but of course, you should start with something more simple