At the gym I have noticed a number of people doing the following.
They jump off the treadmill, or they leave the class before the cooldown.

Cooling down after exercising is just as important as the warm up.
This vital part of your exercise program promotes recovery as well as preventing injuries and helps to reduce delayed onset muscle soreness.

Always replace the fluids lost after a workout.

Stretch your hard working muscles, hold each stretch for 30 seconds, please, please do not bounce.

Have a post workout snack, for example, some chocolate milk or a fruit smoothie.

Have a great evening.