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