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