Ignoring inversions, it's as Anglo said: Adim=Cdim=Ebdim=Gbdim. The four notes in each of those chords are (surprise) A, C, Eb(D#), & Gb(F#). Likewise, Bbdim=Dbdim=Edim=Gdim, and their four notes are Bb(A#), Db(C#), E, & G. Same pattern for B, D, F, & Ab(G#).

Fret your treble E & G strings on the first fret, and play a four-string chord with the B & D strings open, and you have Fdim=Bdim=Abdim=Ddim. Slide the E & G string fingers up to the 2nd fret, and add the two remaining fingers to fret the B & D strings on the first fret, and you now have Adim=etc. Keep all four fingers in relation and slide it up a fret (E & G strings on 3rd fret, B & D strings on 2nd fret), and it's Bbdim=etc. Slide it up again and it's Fdim=etc. again, and so on. I'm away from my guitar and chord diagrams, but I believe the fingering is finger #1 (pointer) on the D string, #2/B, #3/G, #4/E. I hope that's clear (it's a lot plainer with a visual).