The following five examples are two-handed tapping examples on the treble side only. To avoid cluttering the staff line of the treble hand (the hand that usually plays the treble side, that’s the right hand on a right handed instrument) has been written on the top staff and the bass hand on the lower staff - but both hands play on the treble set of strings only.
Technically you could use one single finger on each hand. Of course using multiple fingers works better. Notice how both hands alternate tapping the strings.
This is the initial pattern. As in notation for classical guitar the circled numbers denote string numbers. The lightest string is “1” and from then on numbers increase with string thickness. In our case the string numbers are important to show that both hands occasionally tap notes on the same string.
This is an harmonic extension of example 1.
Same basic idea except we use three strings instead of two. Also note how the treble pattern is essentially 2+2+2 eighth notes while the bass pattern is 3+3 eighths.
Nice melodic pattern with a slightly more interesting rhythmic pattern. Note how the bass hand pattern alternates starting notes because it uses five notes per measure.
Same pattern as example 5 except that the bass hand pattern is played one string lower. This can sound very confusing because of the overlapping notes. But it also shows how an unusual tapping pattern can bring a few simple notes to live.