I keep the landing light or searchlight on all the time, from takeoff to landing, in the daytime. I want people to see me coming. At night, I turn it off when I'm outside the traffic pattern or away from most potential traffic, because it hurts my night vision. I keep all the strobes that are installed on all the time, unless I'm in clouds. I want everyone in the sky to see me, I don't want to sneak up on anyone. If the landing light burns out, my employer has plenty of money to buy more. Better to buy a landing light than a new helicopter and pilots, and lights are the best things available for preventing collisions.
In a past life, I flew formation flights and landings with no outside lights at all, using the instrument lights of the ship I was flying on to maintain position, and landing in formation with no lights anywhere, other than one handheld strobe the pathfinder used to mark the landing area for the lead ship. I still can't believe I was once so young and stupid.
Oh, and PF1, some helicopters can't be started with the nav lights on. On the S76, they don't work until you have at least one engine running. Don't blame me, I didn't design the electrical system on the thing.