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