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