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