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