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