Tuplets are used to subdivide one beat (or more) into equal divisions. In a simple meter like 2/4, you’ll find tuplets with an odd number of subdivisions (triplets = 3 subdivisions of the beat, quintuplets = 5, etc.), and in a compound meter, like 6/8, you’ll see tuplets with an even number of subdivisions (duplets = 2 subdivisions of the beat, quadruplets = 4, etc.)
A simple way to improve your playing is to perform scales using various tuplets. Most musicians are used to playing scales with quarter, eighth or sixteenth notes, but using tuplets will help improve your rhythmic accuracy and hand coordination, not to mention your mental focus and listening skills.
Start with a two-octave scale, such as this G major scale. Play it slowly and use a metronome. Listen to each note to make sure your playing is clean. Use alternating picking for the entire scale, even when changing strings. I prefer to play scales legato, and I will use a clean sound when playing on an electric guitar.
Once you have the 8th note version under your fingers, try playing the same scale using triplets. It will be helpful to count each triplet. Again, use strict alternating picking, and play with a metronome. Notice that, compared to the 8th note scale, different pitches will fall on the downbeats. Also, since each beat is divided into three subdivisions, you will play an upstroke on every other beat. (Note that a couple of notes have been added to the end so that you end on a downbeat. This will be helpful later.)
Now try the same scale using other rhythms and tuplets. Play them slowly and focus on rhythmic accuracy. When counting septuplets, I find it easier to count 1-2-3-4-1-2-3, instead of 1-2-3-4-5-6-7.
Once you feel comfortable with different tuplets, the next step is to practice them in succession. Instead of ending each scale on a quarter note, jump right into the next one using the next tuplet. You’ll need to anticipate the rhythm of the next tuplet. Start slowly so that you can perform all tuplets cleanly and accurately. Septuplets will be hard to play if you start too fast!
How did you do? As you become better at this exercise, you can also try switching up the order of the tuplets. Try playing in reverse from septuplets to 8th notes or choose tuplets in a random order.
Finally here’s a bonus exercise that will test your tuplet playing abilities. Start alternating picking with the 8th notes on beat 2.