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