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