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)(11,17)(12,14)(13,21)(15,19)(16,20)(18,24)(22,23)(25,26,28,31)(27,35,37,40)(29,34,30,33)(32,36,39,38)(1,3,4,8)(2,5,6,7)(10,14)(15,23)(16,21)(17,24)(26,31)(27,36)(29,30)(32,35)(37,38)(39,40)(9,11)(10,15)(12,18)(13,22)(14,23)(16,24)(17,21)(19,20)(25,27,28,37)(26,32,31,39)(29,36,30,38)(33,40,34,35)(2,6)(5,7)(10,14)(11,18)(16,21)(19,22)(26,31)(27,37)(33,34)(36,38) 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.