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