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