Ditto. Helmet a definite neccessity. To stop your sail wipping round as you turn(which tends to tip you over)pull your sheet rope in going into the turn and let it out coming out of the turn. Another way is to grab the boom and force it around as your' going through the turn(stops that suuden wheel lifting thump)
If your front wheel starts to shudder as you turn, slide your body/ballast/weight forward into thw turn and back when turn completed.
A hair net can be useful to stop your hair getting caught in the ropes/pulleys on the back of the seat.