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