Welcome to SRP jtepper.
The chin area is the hardest for many men. I would not go ATG on the chin area. Go WTG and as you get better moving the str8 around on your face go XTG on your chin. Everybody's face is different.
It's important to stretch the skin tight. I either wrap a piece of paper towel around my left index finger or use alum on both hands. Alum helps to grip the razor too. I start my XTG motion right about where you would have a goatee. Little buffing / chipping motions towards the center of the chin.
Always keep the spine or back of the blade down flat against your skin and then adjust to cut whiskers. GO slow like the guys said. As you get better you'll feel frisky and nick yourself. I know I did. It's about the angle. Have fun.
MIke