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