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