Double check that the conditions for flying are still safe (no people entered the flying area without you noticing as you were focused on the model, nose of model is pointing away from you and into the wind, nothing hanging loose from the model): Safety First!
If the flying conditions are still OK, switch the motor on again (throttle stick in lower right corner until the motors start up to idle). Increase the throttle stick until the model gets light on its feet.
Increase the throttle stick a little bit faster so that the multi-rotor copter quickly lifts off. You want it to go to an altitude of 30cm or more to get out of ground turbulence caused by the downward airflow from the propellers. Once you are at 30-50cm, gradually reduce the throttle to slow down the ascent, and gradually decrease it further to descend slowly land again. Do NOT suddenly decrease the throttle or you will crash. If you start descending too quickly, increase the throttle a little bit to slow down the descent.
First landings will probably be “bouncy”, so try to stay between 30 and 50cm height on these first lift-offs. Once you are almost on the ground (centimeters off the ground or just at the moment before touching the ground), decrease the throttle a bit faster to avoid the MK responding too much to ground turbulence and acceleration sensor inputs resulting in repeatedly bouncing. Once on the ground pull the throttle stick back to idle.
If the copter drifts a bit during this phase, just reposition it on the ground between take-offs. We’re not yet going to try flying it back to its position. Practice lift-off and landing repeatedly until you can fully control it and landings are soft and smooth. Reduce the throttle to idle between landings and recheck the environment!
If for some reason something goes wrong and the copter lands on its side or upside down, IMMEDIATELY turn off the motors (throttle stick in bottom left corner until the motors stop) to avoid unnecessary damage to ESCs, propellers or motors). Reposition it, and check for damage. Reposition yourself and recheck the environment. Restart the motors (throttle stick in bottom right corner until motors start) and restart lift-off and landing practice.
Repeat take-offs and landings until you are confident that you can land your multi-rotor copter smoothly without bumping or bouncing around.