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