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