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