One vertex per element, one color per generator, with an edge from x to x·s.
(1,2)(3,4)(5,6,8,7)(9,10)(11,20)(12,15)(13,28)(14,27)(16,19)(17,22)(18,32)(21,33)(23,36)(24,25)(26,30)(29,40)(31,35)(34,38)(37,39)(9,11,15,23)(10,17,12,25)(13,29,31,38)(14,24,16,22)(18,34,26,40)(19,36,27,20)(21,32,37,30)(28,39,35,33)(2,4)(5,7,8,6)(9,12,15,10)(11,20,23,36)(13,26,31,18)(14,27,16,19)(17,22,25,24)(21,34,37,40)(28,32,35,30)(29,39,38,33)(2,4)(9,13,16,32,15,31,14,30)(10,18,27,28,12,26,19,35)(11,21,24,38,23,37,22,29)(17,33,36,40,25,39,20,34)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.