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