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