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