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