Roborock S6 Using the mopping function 

0:03 -Wet the mop cloth
0:05 -Wring the cloth until it is damp but not dripping
0:09 -Select water-flow speed.
0:11 -Attach the mop to the water tank
0:16 -You can also use the disposable mop.
0:22 -Open the water tank and fill with water
0:31 -Slide the water tank under the robot until it clicks in place
0:34 -After mopping, slide off the water tank