Yeah, either play around first with the settings, watch some tutorials, or just learn on your own, but practice making signatures first.
In before I had dozens of rejects before I made the nice ones of my sigs. (Note: Haven't made a sig in a long time too, so my skills have been a little bit rusty)
Once you get a little bit used to it, you should try an advanced program, like GIMP. And yeah I also recommend GIMP for a program, but any "good" image editing programs, other than Photoshop, is really nice to practice on. I tried practicing on PaintNET, it got better on it. XD
An advice for effects: Make the effects get along with the Render, a good flow in the signature, even the simple ones, make it stand out, if you know what I mean.