How to implement PID or simular?

Are currently trying to get my little segway model to balance. I'm having trouble to figure out how exactly to do that with the available data. I have current angle, current angle velocity and I can set a motor speed from 0 to 255. What is the correct approach to solve this? A PID?

The Segway: Theory
Balancing robot for dummies
arduino - segway

Thanks!