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