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