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