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