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