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