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