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