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