Hi, and faces are hard - any helpful tips?

I'm making a map (aren't we all) and I'm having trouble getting faces to look right, basically. I'm trying to skin the old warden model (the one from the RoC campaign) to look like blood rayne, and I've only actually started skinning stuff for this map, so my skills are a bit basic, I've had a quick look around, but I haven't found anything that gives me some advice on how to do skin well. Basically I'm looking for any tips, or helpful suggestions, or maybe a point in the right direction, I just want to improve.

This is the sort of level I'm at with skinning (see attacked file) this is my best skin I recon.

Use the old fac as guide. Like the eye sockets nose and mouth. They will be give you the general placement. Try to get a picture of someone. You see that light touches mostly on the forehead, nose, cheeks, and chin. Other areas should be shaded. Remember the face has wrinkles near the eyes and forehead. Just keep trying you get better and better.

Thanks, that was kinda what I was trying to do, but I found it hard, I piant 40k and stuff like that so it's probably just a matter of getting the hang of photoshop's tools and getting a feel for what things look like in-game. I'll keep plugging away at the skins, thanks a lot for the suggestions and advice.