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