Do the harmonics of the following;
5th string at the 7th fret.
6th string at he 5th fret.
Adjust the tuning once you hit both the same time.
Once its really in tune, do the harmonic for the 5th string, 7th fret, with the fretted 6th string at the 17th fret.
The idea is to confirm that the strings are tuned, which is a baseline for the intonation.