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