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