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