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)(13,16,21,22)(18,19,23,24)(25,26,31,34)(27,32,37,38)(28,36,39,33)(29,35,40,30)(1,3,5,8)(2,6,4,7)(25,27)(26,32)(28,30)(29,36)(31,37)(33,40)(34,38)(35,39)(10,15)(11,17)(16,22)(18,23)(25,28,31,39)(26,33,34,36)(27,35,37,30)(29,38,40,32)(1,2,5,4)(3,6,8,7)(9,11)(10,12)(13,18)(14,17)(15,20)(16,19)(21,23)(22,24)(25,28)(26,33)(27,30)(29,38)(31,39)(32,40)(34,36)(35,37)(1,2,5,4)(3,6,8,7)(9,12)(10,11)(13,19)(14,20)(15,17)(16,18)(21,24)(22,23)(25,29,31,40)(26,30,34,35)(27,36,37,33)(28,38,39,32)(1,4,5,2)(3,7,8,6)(9,13,14,21)(10,16,15,22)(11,18,17,23)(12,19,20,24)(25,30)(26,29)(27,28)(31,35)(32,36)(33,38)(34,40)(37,39)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.