Take your sample off the microscope stage and clean all lenses you have been using for your experiments thoroughly with the Whatman lens cleaning tissue provided.
Close the Leica LAS X software and shut down the PC
Turn the laser emission key in the OFF position, then turn off the switches next to it from right to left (Laser Power, Scanner Power, PC – Microscope).
If you used any of the the STED lasers, turn the STED laser keys 1/4-turn anticlockwise to the OFF position.