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