I think one of the most effective ways is to memorize the notes on the E & A strings and then apply those one and two octaves up.

Once you know the notes on the E string, for example, you only need go up 2 strings (to the D string) and 2 frets to find the same letter note one octave higher. Then, from the D string up 2 strings (to the B string) and 3 frets to find the next highest octave of the same note.

Same thing on the A string leaping over to the G string (2 frets higher) and then the high E string (3 frets higher).