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