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