Integrity is how you work the half hour after the manager goes home.

Unsupervised time is where your real standard lives. Anyone can work well while being watched, so the hour after the keys are handed over and nobody is checking is the only honest measurement available. What you do then is also what you will do when you are the one in charge. The habit is being set now, cheaply, in a job you will not keep.

Treat the last stretch of your next shift as the part that counts. Finish the closing list properly, wipe the thing nobody inspects, and leave it better than you would if the manager were there.