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