Welcome to the trade. Get used to long hours and not always having time for lunch. Like the pros have said:
-No texting on the job. I set a ring tone for certain people and the shop so I know when that ring comes that its important. If you need to make a call ask the journeyman first so he knows what you're up to.
-Hands out of pocket
-Get used to what has to be done and start getting the tools in place as theyre needed. Example: the copper pipes for the A/C have been run. Get the torch before hes done laying his pipes out. After that grab the vacuum pump and a set of a gauges and the extension cord if needed. And maybe the caulking or spray foam to fill the hole for where the pipes go in.
-Always have something in your hands. If youre going to the truck take some garbage or something the tech is done with. Eventually you will get to know the codes and requirements and if you see something small just do it. In my experience, showing initiative and doing without being told at the right time REALLY will get the journeymen wanting to take you along. By right time I mean dont start running control wire when the new furnace isn't even in place.
-Above all the best rule for the new guy. IF YOU DONT KNOW- ASK!!!! They know you hardly know anything. IF you don't know what you've been asked to do rather than attempt it just admit you don't know how to do it and that is when you will learn how to do it.
All and all the right attitude and right ethic will leave the trucks waiting for you. IF they aren't waiting well....maybe its time for a new line of work?