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