Never touch them with your fingers or a Q-tip. Only touch them with a chamois stick while cleaning and then only in a horizontal direction. Cleaning the video heads is the most critical part of the process. Use extreme caution. Never use cotton swabs.
Cotton tends to grab, get caught or leave fibers in the heads.
It can also break them. Using chamois sticks is by far the safest method. Soak a chamois stick with head cleaning fluid and place it directly on a video head with light pressure. For beginners, the safest method involves holding the chamois stick stationary in one hand and rotating the drum clockwise with the other. You want all scrubbing action to be in a horizontal direction.