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