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