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