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