When using the Zerostat on a record, I've had fine success doing it both with the record on the platter and in my hand. Try it both ways and see what's most effective for you. Holding the record in your hand certainly removes the risk of accidentally aiming it at your cartridge, but I've not had a problem using it with the LP on the platter - just being careful not to point the nozzle at the cartridge. Either way, move the nozzle in a circular motion around the surface of the record as you squeeze the trigger.
Follow Larryi's recommendation for the squeeze technique, and keep the nozzle about 6" from the surface. Someone in an earlier thread shared the instructions that came with his Zerostat to point the nozzle away from the record when releasing the trigger. I'd always done it as Larryi describes: keeping it pointed at the LP at all times. Since that thread, I've experimented with pointing it away on the release and that seems to work well.
I think the key factor in all of this is to experiment and find what works consistently for you. FWIW, notwithstanding all the discussion, I find the Walker Audio Talisman to be my tool of choice at this point for each LP play, and the Zerostat stays in the cabinet.
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