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