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