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