Walker, 32, joined Manchester City from Tottenham Hotspur in a £45m transfer six years ago.
He has appeared for England 73 times, including at two World Cup finals.
Asked what advice he gives to younger players, Guardiola added: "They know it already. When you open the door at home, you have to know you will be filmed whatever you do, it's part of society."เว็บตรงคาสิโน