Every fingering that fits a hand
5766
moderate
5363
hard · no 5
5366
hard · no 5
536x
easy · no 5
What is true of it
Cm7 is C, E♭, G and B♭ — 1, b3, 5 and b7 counted from C.
These are also the notes of E♭6/C and D♯6/C. Which name is right depends on what is underneath and what came before — the notes alone do not decide.
On an instrument that cannot reach all 4, the 5 goes first, in that order.
The easiest of the 4 fingerings below is 5766: 4 fingers, held at the 5th fret.
None of them uses an open string, so this chord moves up the neck unchanged — the same shape 1 fret higher is the chord a semitone above.
Where its notes are on the neck
The brass dots are C, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
Cm7/E♭
8a8a
Cm7/G
0363
Cm7/B♭
3333
An inversion is the same chord with a different note lowest. The name changes to a slash name because the bass is what a listener hears as the foundation.