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