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