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