I bought the lowest end CO2 regulator from Northern Brewer and I have no idea how to set the PSI. I know there is a screw, but whenever I turn on the CO2 the gauge just keeps rising. The gas never stops going in the keg until it is over pressurized. I feel stupid cause all I do is blast it until the pressure is reached then I turn off the CO2. I repeat as pressure drops every few beers cause I don't know how to set it. Get me simple directions please, I am very slow apparently.