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