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