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