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