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