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