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