How do you add freon to 1992 Lexus sc400 coupe?

Using a set of a/c gauges put the blue hose on the low side (suction side) and the red hose on the high side (discharge side) then connect the yellow hose from the gauges to the service port on the can of freon.....

During the recharging process remembering to keep the low side readings between 30 to 40psi and the high side between 200 to 250psi depending on the outside temperature……………