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