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