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