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