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)(15,18)(16,17)(19,20)(21,22)(23,25)(24,31)(26,27)(28,32)(29,35)(30,36)(33,34) involution — undirected(5,7,10,8)(6,11,12,9)(13,15,17,20)(14,18,16,19)(22,27)(23,29)(24,32)(34,36)(6,12)(7,8)(14,16)(18,19)(21,23,26,29)(22,25,27,35)(24,33,32,30)(28,36,31,34)(1,2,3,4)(5,8,10,7)(6,11,12,9)(13,16,17,14)(15,19,20,18)(21,24)(22,28)(23,30)(25,34)(26,32)(27,31)(29,33)(35,36)(5,9,10,11)(6,7,12,8)(13,15)(14,18)(16,19)(17,20)(21,25)(22,23)(24,34)(26,35)(27,29)(28,30)(31,33)(32,36)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.