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