Every fingering that fits a hand
5035
easy
x035
easy
5233
moderate
5235
moderate
523x
easy
What is true of it
Csus2 is C, D and G — 1, 2 and 5 counted from C.
These are also the notes of Gsus4/C. Which name is right depends on what is underneath and what came before — the notes alone do not decide.
The easiest of the 5 fingerings below is 5035: 3 fingers, held at the 3rd 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
Csus2/D
x233
Csus2/G
0035
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.