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