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