When making a signature, there are a few 'rules of thumb' that I advise you to follow in order to come up with something great. While this is not a definitive list, it encompasses the most basic principles of signature making.
My Top Tips
1) Don't rush
Take your time. Rush work is one of the greatest failings of many artists. Don't start a sig without being willing to spend at least 3 hours perfecting it.
2) Layer
Be sure to put absolutely EVERYTHING in a separate layer. This ensures that you can always correct mistakes without having to start from scratch.
3) Start simple and work from there
Trying to use complex techniques is a major no-no for first time signatures. Playing with C4D's and animations is not wise for your first sig.
4) Don't be lazy
Never use someone else's work as your own. Only use someone else's PSD's as a way to learn what techniques were used.
5) Invest time looking for quality images
Never use images found on google unless they are of hideously good quality. DeviantArt is a good place to look, although don't do the lazy thing and use someone else's PSD's and textless signatures.
6) Add depth
It's an important factor of sig making, and will make your sig look a hundred times better.
7) Use flow where possible
Making signatures flow will make it easier on the eyes, and will often direct the viewers attention towards the focal points of the sig.
8) Use text sparingly
Signatures dominated by text are terrible. If using text, make sure it is no more than size 10 and is a colour that is in the sig, so it won't stick out too much.
Explanations
Stocks
A stock is a ready-made picture, which you add effects to..
as opposed to a render, where you build the background, and add a pre-cut picture to it.
Example: Stock-made sig
Flow
Flow means which direction the whole sig is going in.
This can mean which way the C4Ds/Brushes point, and which way the text is slanted.
Example 1: A sig
with flow
If you'll notice, the render is leaning to the right a bit. So, all of the effects [for the most part] are leaning in that same direction.
It helps to guide the viewer to where the focal is.
Example 2: A tag
without flow
As you can see, there is no general direction in which the sig travels
or guides the eye.
Sometimes, flow isn't really necessary, as in a sig that is meant to be chaotic [like a messy grunge tag, or the like.], but most of the time it makes for an overall better looking tag, that seems much more well thought out.
The general rule is to
guide the viewer's eyes to your focal point.
Depth
Depth means showing the focal point off. The best way of this is to blur the background (Filters> Blurs> Blur), so the render stands out. Another way is to make a new layer over the top, set it to softlight, and brush the light parts of the sig in white, and the dark parts in black. Sometimes, with a bright render, you can duplicate the render's layer, and set it to overlay, then play around with opacity.
In short:
Depth helps show your viewer what they should truly focus on,
while Flow guides them there.
Example:
Take a look at the top chess image. Notice that the chess pieces are all equally clear.
Now take a look at the bottom chess image, see how the pieces in the back are blurry, while the ones closest to the viewer are clear?
This is creating the sense of depth.
The easiest way to do this is, after you've finished the sig [Or whatever you are working on], but before you add text, create a new layer. Then go to Image >> Apply Image.
After that, take out your blur tool, or sharpen tool, and just experiment. Just remember the key rule:
The closer to the focal point an object is, the sharper and clearer it is. The further away it is, the blurrier it is..
Again, experiment, but
don't over do it.
C4Ds (Cinematic 4-Dimensional Renders)
A C4D can be used to add depth, flow, color and much More to a signature.
When you first use them they may Seem to chaotic but as you begin to understand their usage And incorporate them into your sigs better you will find That they are very valuable assets. One important thing that you will want to remember is to use them in moderation. By this I mean don't fill the entire background of a sig with them like you would have used brushes when you were just starting. Use them to add flow to the image. Overusing them will make the whole sig way to chaotic and can easily ruin an entire sig.
These are very useful to enhance things, but in my opinion, they work best with stocks.
They are abstract renders (that is to say pre-cut pictures, made with the Cinematic 4D programme). Set these layers to dodge, softlight or screen for the best effects, but still experiment.
Example:
I hope these tips will help you.
Disclaimer
I did not create any of the images used in this tutorial, but I am using them for the purposes of demonstration.