One vertex per element, one color per generator, with an edge from x to x·s.
(2,7)(4,5)(8,15)(9,10)(11,16)(12,14)(17,18)(19,26)(20,28)(21,24)(22,31)(23,25)(27,30)(29,32) involution — undirected(1,2,6,9)(3,11,13,15)(4,10,5,7)(8,14,16,12)(17,19,23,29)(18,20,25,30)(21,28,22,27)(24,32,31,26)(1,3)(2,8)(4,12)(5,14)(6,13)(7,11)(9,16)(10,15)(17,20)(18,19)(21,26)(22,32)(23,30)(24,27)(25,29)(28,31) involution — undirected(2,9)(7,10)(8,16)(11,15)(17,21,23,22)(18,24,25,31)(19,27,29,28)(20,26,30,32)A Cayley diagram is a choice, not a fact about the group. Another drawing of this group — in a book, or on a different generating set — may look nothing like this one.