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