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