Hey Paul,

Did you check out the Wiki section on ways to hold a razor?

Different ways to hold a straight razor - Straight Razor Place Wiki

I've been learning using one hand too (still a newbie less than 10 shaves in), and I think it helped when I started thinking about different holds to get the different spots...basically I experiment until it feels like I have a lot of control over the razor in whatever position or angle it needs to go to shave that part of my face.

I never thought about practicing with the spine of the razor against my skin...I'll have to try that, thanks!

HTH
--nick