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