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)(11,17)(12,13)(14,18)(15,21)(16,22)(19,24)(20,23)(25,26,30,32)(27,31,35,40)(28,33,37,39)(29,34,36,38)(3,7)(5,8)(9,11)(10,15)(12,19)(13,20)(14,21)(16,24)(17,18)(22,23)(25,27,30,35)(26,31,32,40)(28,36,37,29)(33,38,39,34)(1,2)(3,5)(4,6)(7,8)(12,22)(13,16)(19,23)(20,24)(26,32)(27,35)(28,37)(34,38) involution — undirected(9,12)(10,16)(11,19)(13,18)(14,22)(15,24)(17,20)(21,23)(25,28)(26,33)(27,36)(29,35)(30,37)(31,38)(32,39)(34,40) involution — undirected(1,3)(2,5)(4,7)(6,8)(9,11)(10,17)(12,23)(13,20)(14,21)(15,18)(16,24)(19,22)(25,29,30,36)(26,34,32,38)(27,37,35,28)(31,39,40,33)(1,2)(3,5)(4,6)(7,8)(9,13,14,16)(10,12,18,22)(11,20,21,24)(15,19,17,23)(25,26)(27,31)(28,33)(29,34)(30,32)(35,40)(36,38)(37,39)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.