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