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