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