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