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