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