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