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