There is a connector on the starter solenoid with four ¼” tab terminals. The mating connector has three wires and one empty position. I connected to the empty tab with a mating socket and 18 awg wire routed to the front of the bike. This effectively connects to the battery through the 10A fuse (important detail IMO). Then, I mounted a switch right next to the meter with a little z-bent piece of aluminum sheet metal and attached this with one of the M4 meter mounting screws. The wire mentioned above is then connected to the center pole of the switch. The switched pole is then connected to the turn signal flasher plug which is empty on my bike. You need to select the bike power side of the flasher plug and connect with another ¼” tab terminal. No part of the bike wiring harness is modified in any way. All the bike plugs, including the meter, are connected normally. Nothing is disconnected. When the switch is ON, everything connected to this circuit is powered up. This includes the meter but not the headlight. I have left the switch ON for a week and the battery has not dropped at all. I hope that the sleep mode draw is low enough so that the switch can be eliminated. Time will tell.
P.S. – I think the sleep mode current I measured before was not “deep” sleep. Some devices go to deep sleep after prolonged inactivity and draw only micro current. I hope the Beta meter works this way.