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