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