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