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