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