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