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