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