Although the 3rd and 7th of a chord are the most common guide tones, there are other notes in various types of chords which can be important in indicating the particular chord type- In triads, this can be the 5th, which can indicate a diminished or augmented chord when combined with the 3rd of the chord. In 6th chords, the 6th degree is a guide tone as demonstrated in the following example.
All the upper extensions of a chord (9ths, 11 ths and 13ths) can also be used as guide tones. The 13th degree is the same as the 6th. This means that the 7th of the chord is also necessary to distinguish a 13th chord from a 6th chord.
The more notes there are in a chord, the more possible guide tones it contains. In a seventh chord there are two# but anything higher contains three. The fact that there are more guide tones can make it easier to create a smooth line between chord changes. In the following example, the note G becomes a different degree in each new chord, as shown between the notation and the TAB. The better you know the degrees of all chord types in all keys, the more creative you can be with chord progressions.