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