^^ With experience in mind.
For a first sig... Well, it's one of the better first sigs I've seen.
The effects are pretty cool. I wouldn't work with text for a while, though; even for experienced graphic artists, the text can easily make or break the sig - more often the latter than the former.
Something to work on for the future is blending. In my opinion, blending is key in making art. Make sure there's depth to your signature: background and foreground. Then, just blend in your focal wherever it belongs (usually between the background and foreground, although it can sometimes be the foreground or background).
In here, the focal is the foreground. You did a decent job with blending for your first time, actually. But typically you want to align the lights/shades with the light source, and colors should respectively match/blend. If you look at your focal, you see that the light source should be coming from our right. However, your light source in the signature is to the left of the focal. Thus, the blending is a bit off. This can be solved by moving the focal over the left side of the sig, but now we move on to another issue.
People may say never to center your focal, but I say never to put it off to the side. In either case, the argument is that it distracts the audience from the focal, but in my opinion, it just doesn't look good. I don't mind centering, but it's more fun to play around with placement.
This isn't much of a critique, but rather just suggestions for the future. Experimentation is a huge part of art; feel free to play around with tools and brushes and mess around with how you use them. You can always use Control+Z (or Edit > Undo) if you don't like the result. For your first sig, you did a pretty decent job.
Avatar: In memory of ieatwyverns <3
Thank you, Vasco <3