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