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