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