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