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