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