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