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