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