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