Booking out at small airfields
I'm going to be sitting the PPL skills test soon(when this bloody weather settles down!), and i was just wondering, with regards to booking out at smaller airfields(which my instructor has always done on my behalf). For, let's say a one hour VFR flight, do you just trot into the tower and tell them of your intentions? This may seem daft at my stage of training, but it's always been done for me. Even dafter when i've already booked out at a major international(ish) airport when on my cross country qualifying.
Also, is it always necessary to do it on the ground for relatively short flights, say for sightseeing?