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