If you start a lap, you can finish a lap.
Pushing off as hard as you can, at the beginning of a length, is not cheating. It’s resourceful.
One more lap never hurt anybody.
You can always just stop, at anytime.
Kickboards are for in-between swimming laps, and modesty when emerging from the pool.
Wear your shoes into and out of the pool.
It is okay to switch strokes in mid lap, as long as you keep the pace.