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