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