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