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