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