A commonly-used voicing for a Major Seventh Chord is to play the root in your left hand and the triad formed by the 3, 5, and 7 in your right…
One might conceive of this CM7 voicing as Em/C…


Homework
Using your ears and knowledge of scales and chord structure, “transpose” this voicing to all spellings in three musically-useful patterns:
- Chromatically Ascending: C > Db > D > Eb > E > F > Gb > G > Ab > A > Bb > B > C.
- Chromatically Descending: C > B > Bb > A > Ab > G > Gb > F > E > Eb > D > Db > C.
- Cycle of Dominants: C > F > Bb > Eb > Ab > Db > Gb > B > E > A > D > G > C.
Doing so will develop an enormous chord vocabulary that you will know by ear, intellect, eye, and muscle… laying a rock solid foundation for fluent improvisation.