One vertex per element, one color per generator, with an edge from x to x·s.
(2,4)(5,6)(7,14)(8,12)(9,18)(10,13)(11,17)(15,20)(16,19) involution — undirected(5,7)(6,11)(8,15)(9,16)(10,17)(12,19)(13,14)(18,20)(21,22,26,29)(23,30,33,35)(24,28,31,25)(27,34,36,32)(1,2,3,4)(5,8,10,9)(6,12,13,18)(7,15,17,16)(11,19,14,20)(21,23,31,34,26,33,24,32)(22,27,28,35,29,36,25,30)(5,9,10,8)(6,12,13,18)(7,16,17,15)(11,19,14,20)(21,24,26,31)(22,28,29,25)(23,32,33,34)(27,35,36,30)(7,17)(11,14)(15,16)(19,20)(21,25,24,29,26,28,31,22)(23,30,32,36,33,35,34,27)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.