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