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