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