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