Most important here is to stop mixing the gas and air... not necessary and will damage something costly if you keep doing it!
Follow this list and you should be all set:
1) Disconnect the meter from the meter bar and cap the outlet as directed at post #3... see image again. This is critical to success.
2) Disconnect all union fittings to each gas appliance and cap these (remove the 1/2 union fitting and cap line). You could also shut off the shutoffs, but as stated earlier, if you have a leak past a shutoff it could damage a gas valve or even damage the appliance.
3) Install test apparatus with shutoff and gauge at new piping to appliance.
4) Pump the system up to 10 PSI and hold for 20 minutes. Once confirmed all is OK you will need to schedule for inspection.
5) Pump system back uyp and stand for inspection... pass inspection...
6) After the inspector signs off on the test you can depressurize the system by opening the shutoff at the appliance and removing the test apparatus
(do this slowly).
7) Reconnect the gas meter and all the appliances (or turn on shutoffs you shut off).
8) Double check all connections that you disturbed to be sure ALL unions/fittings have been re-tightened.
9) Turn on gas at gas meter now
10) Bleed gas off at the farthest appliance by loosening the union fitting until you smell gas (shouldn't take too long). Re-tighten union. This expidites lighting the pilots.
11) Bleed off gas in same manner as above at any appliance you disconnected. Be sure to let gas dissipate before lighting the pilot(s) in next step
12) Light pilots or test that stoves ignite at each burner, etc.
13) Sit back and have a beer...
Job well done!