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