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