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