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