You could make a small graphic image.

You could pick a font, create your signature and use that consistently.

You could do both as above.

You could get a marker, create a signature ( I mean actually sign your signature), scan it, save it as a graphic and then apply to your image. The marker is bigger than ball-point pens and allows for color changes and effects.

 

I have a graphic that I made and apply to images when I post images of characters I made up. I also have a font selected and just change the year (2010, 2011, 2012 for next year) all it says is (C) Derek L. Furman 20xx. With the graphic (as with the font), you can scale it, change the opacity, etc.

It all depends on how you want your signature to look.

"Few are agreeable in conversation, because each thinks more of what he intends to say than that of what others are saying, and listens no more when he himself has a chance to speak." - Francois de la Rochefoucauld

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