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