Listen to as much merengue as you can to get a feel for the distinct rhythm. You can find these recordings at specialty music stores or online (see Resources). You can also find merengue sheet music at the same locations.
Always play in cut time (2/4), which means there are two beats of music to the bar. Merengue is played fast and at 2/4 time, which establishes its particular tempo and rhythmic patterns.
Master the quintillo, which is the fundamental and recognizable rhythm figure for a merengue. The drum will typically characterize this figure by playing five quick beats in succession between the second and third beats.
Brush the guira on every downbeat of the music, softly, primarily to keep time. More complex patterns can be added for effect, but the steady brush is best, broken occasionally by a skipped beat where one is expected.
Play the tambora with your hand on one side and with a stick on the other, creating two distinct sounds that complement the merengue.
Consider adding a saxaphone or clarinet to the traditional mix, as many modern merengue bands have begun to do.