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