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