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