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