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