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