Sample juices. Various strengths and flavors. Try things because it usually takes a few to find your tastes & required strength.
PT is a good idea if your not on the go most of the time. Use one with a battery if you want to plug it into your computer. Get a wall to USB adapter if you want to try one without a battery and more voltage. (Voltage you get is dependant on the resistance of the atomizer multiplied by the current allowed by the USB port and most motherboards have a fairly low current limit.)
Read up on the proper way to vape while you wait for the mailman because smoking a PV is seldom a good thing.
Have fun! I don't know how to order that, but it's important too.