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)(11,16)(12,17)(13,18)(14,15)(19,23)(20,21)(22,24)(25,26,31,34)(27,32,30,28)(29,33,39,40)(35,37,38,36)(1,2,5,6)(3,7,8,4)(9,11)(10,16)(12,19)(13,15)(14,18)(17,23)(20,22)(21,24)(25,27,31,30)(26,32,34,28)(29,35,39,38)(33,37,40,36)(1,3)(2,4)(5,8)(6,7)(10,14)(11,13)(12,20)(23,24)(25,28,31,32)(26,27,34,30)(29,37,39,36)(33,38,40,35)(1,4)(2,3)(5,7)(6,8)(9,12,15,20)(10,17,14,21)(11,19,13,22)(16,23,18,24)(25,28)(26,27)(29,37)(30,34)(31,32)(33,38)(35,40)(36,39)(1,2)(3,4)(5,6)(7,8)(9,13,15,11)(10,18,14,16)(12,19,20,22)(17,23,21,24)(25,29)(26,33)(27,35)(28,36)(30,38)(31,39)(32,37)(34,40)(1,4)(2,3)(5,7)(6,8)(9,14,15,10)(11,18,13,16)(12,21,20,17)(19,24,22,23)(25,30,31,27)(26,28,34,32)(29,38,39,35)(33,36,40,37)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.