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)(21,22,27,29)(23,30,33,36)(24,25,26,34)(28,31,35,32)(1,2,3,4)(5,8,10,9)(6,12,13,18)(7,15,17,16)(11,19,14,20)(21,23,26,32,27,33,24,31)(22,28,25,30,29,35,34,36)(5,9,10,8)(6,12,13,18)(7,16,17,15)(11,19,14,20)(21,24,27,26)(22,25,29,34)(23,31,33,32)(28,30,35,36)(7,17)(11,14)(15,16)(19,20)(21,25,26,29,27,34,24,22)(23,30,32,35,33,36,31,28)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.