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