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