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