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