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