This is what I use for some of my sigs. :P First Get out the bg you're gonna use.

2) Go to your layers panel and click on the

and then go to Color Balance.

3) Enter any these:
Shadows: 50/0/0
Midtones: 50/0/0
Highlights: -8/28/-5

Then you should get something like this...

After that, put your text under that so that it matches the bg color. (make sure it's a light grey.) You should get something like this:

Layers like this:

Enjoy. =D