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