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