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