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