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