The problem with most of those signatures you see in that google image link you provided are not c4d signatures. Most of them are just photoshop. I have yet to find a really decent tutorial on the power of C4D for signatures.
One piece of advice I was taught during graphics classes was; When following a tutorial - Don't copy it exactly. Mess with the settings and change things. That way you'll learn what the settings actually do, rather than blindly following the instructions and waiting for the end result. Trial and error, find what works, how it works, mess with it and then your imagination is your only limitation.