One vertex per element, one color per generator, with an edge from x to x·s.
(2,7)(3,5)(8,15)(9,10)(11,14)(12,16)(18,24)(19,26)(21,22)(25,32)(27,28)(29,31) involution — undirected(1,2)(3,7)(4,12)(5,9)(6,10)(8,11)(13,15)(14,16)(17,18,23,19)(20,28,30,32)(21,26,22,24)(25,31,27,29)(1,3,6,5)(2,7,10,9)(4,11,13,14)(8,15,16,12)(17,19,23,18)(20,27,30,25)(21,26,22,24)(28,29,32,31)(1,4,6,13)(2,8,10,16)(3,11,5,14)(7,15,9,12)(17,20)(18,25)(19,27)(21,31)(22,29)(23,30)(24,32)(26,28)(1,3,6,5)(2,9,10,7)(4,11,13,14)(8,12,16,15)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.