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