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