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