I've allways had a rig in my vehicle.Even though I don't have a callsign I use it more like a scanner and listen in.
One time I broke down in the middle of no where and my cell was useless,so I got up on the net and did a general distress call,sure enough they were able to lend a hand and commended me on propper radio procedure
Even if you don't have a license yet it's still good to have a rig tuned in to listen how things work.After a while you do get the hang of it and when you do get the callsign it makes things a bit easier.