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