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