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