Does it need some improvements? I am new at this, but this is my best work.

Looks good - what program did you use to make it? I'd recommend making your font a bit bigger, and making the sig more streamlined.. make it shorter and fatter, give it a bit of elegance. A thin white&black border looks really good on this forum skin. If you're not using GIMP, I recommend you give it a go. You also might want to check out a few other topics and users here and try to emulate signatures you like - also good for getting your imaging skills up.