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