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