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