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