To gas your kegs of home brew beer correctly, your kegs must be cold, this is a must, as the brew will not accept and asorb gas into the beer when hot.
It is best to have your fridge set to around 4 C.
Never set the fridge below 1 C.
Once that your keg is cold you can apply the Co2 gas to the keg for approx 2 days (48 hours) on the pressure 230 Kpa (32 Psi).
It is best to leave the keg for a period of time to allow the gas etc to settle.
Test for correct carbonation.
After charging your keg, decrease the pressure to the approximate dispensing pressure 70 Kpa (10 Psi).
You may need to refine the times given after you have sample your drop, depending is your brew is overcarbonated or undercarbonated.
When charging your keg on higher pressures other than pouring, always ensure that you beer line is not connected to the keg.