Signature tutorials??

[Koyuki]

Use the lasso tool and make shapes. Then add strokes or something. You'll find lots of tuts on good-tutorial.

Just try to learn stuff by messing around with photoshop. And read tuts, you'll learn stuff.
I'm mostly self-learned, but catched some cool stuff from tuts.

Just hang in there

[PossiblE]

Lasso tool, I create the general outline shape, then I use the lasso to make the smaller lines inside.