The pegs are what you will turn in order to change the pitch of the strings. Which direction you turn them can often vary between instruments, so experiment. Directionality is usually the same for the pegs on a single side of the instrument. Tighten the strings to raise the pitch. Loosen the strings to lower the pitch. Absolutely do not tighten the strings too much. This can break your instrument, and the strings may snap off.
