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