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