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