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