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