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