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