Every fingering that fits a hand
1242
moderate
x875
easy
What is true of it
G♯dim is G♯, B and D — 1, b3 and b5 counted from G♯.
The easiest of the 2 fingerings below is 1242: 4 fingers, held at the 1st 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 G♯, the root. Everything else is a chord tone with its degree printed in it.
With a different note underneath
G♯dim/B
4242
G♯dim/D
x242
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.