I want to stress treating the practice plate like a piece of scrap paper. Feel free to doodle on it just as you would a sheet of scratch paper, as if you were learning how to use a pencil or paint brush. Later, when you feel comfortable and more confident with the graver, you can make a more formal plate for presentation.
Start with some straight line cuts that taper in and out evenly. This is going to help you learn to coordinate the foot control with hand movement. Set the AirGraver length of stroke so that half to 3/4 of the first exhaust hole is showing, and set the drive regulator (the regulator on the right) to 25 to 30 psi.
Note: the metal used in these videos is from OnlineMetals.com. It is 2"x 3"x 3/8" thick (1018 cold rolled steel). The plate is as received from OnlineMetals, with no extra preparation of the finish. If you want a better finish for a presentation plate, you can take the time to sand (by hand or with a belt sander) through the sandpaper grits, but for scrap practice plates this isn't necessary. More info on practice plates
Straight line video: Tutorial1a.wmv
Flared arc cut
Now we start to put the cuts together to form some motifs. First do an arc cut and flare it some if you like, and add a small radius arc top to it. The small cut is the same arc cut we have been doing, but not as deep. Video
The first two cuts in this are the same as above but now add an additional gentle flared 'S' and another arc to form a leaf. Video