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