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