Applying the Tremolo to a melody

First, the melody in it's essential form (just the first few bars):
Recuerdos de la Alhambra

Now let's energise the melody by repetition:
Recuerdos de la Alhambra

The practical version for guitar. At moderate tempos the missing note in each group is not perceived by the listener.
Recuerdos de la Alhambra

The right hand fingering.
Recuerdos de la Alhambra

This page illustrates an excerpt from "Guitar Playing and how it Works"

Guitar Playing and how it Works by Peter Inglis
Guitar Playing and how it Works