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