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