How do I get a client to actually show up and try?

You know the exercises cold. The hard part was never the plan; it is getting a real human to show up and push when they would rather not. That gap defeats a lot of good coaches. It does not mean you are doing it wrong. It means motivation is a different craft than knowledge. People do not move because you have the right program. They move because showing up got easier, smaller, and tied to something they actually care about. A client who will not do an hour might do ten minutes. A client with no reason will quit; a client with their own reason will find a way. Before the next session, ask one question: why does this matter to you, in your own words? Write down what they say. Then shrink the first step until it is almost too easy to skip. Momentum, not willpower, is what you are building.