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