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