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