How do you turn compressor on while recharging?

To turn the compressor on while recharging the air conditioning system, first ensure that the vehicle's engine is running and the AC is set to the maximum cool setting. Then, switch on the AC to activate the compressor, which will allow the refrigerant to circulate through the system as you recharge it. Monitor the pressure gauges on the refrigerant can and manifold to ensure proper levels are maintained during the process. Always follow safety precautions and manufacturer guidelines when handling refrigerants.