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