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