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