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