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