Store Button State

Im not trying to cross post…but thought I would make this a direct question for the sake of others;
How do you store the state of a button ie

1. The user presses a button(1) which activates a mode.
2. Another button(2) cycles modes within a certain range eg 1-4.
Lets imagine the mode is now number 3.
3. The user then navigates away to another button(3) which calls up another mode and completes come operations there.
4. The user now presses button(1) again and I want them to land at the last mode related to that button which should be number 3.

How would this be best accomplished?