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)(25,26,31,36)(27,34,29,32)(28,33,37,39)(30,35,40,38)(1,2,5,6)(3,7,8,4)(9,11,14,19)(10,15,12,17)(13,18,21,24)(16,22,20,23)(25,26,31,36)(27,34,29,32)(28,33,37,39)(30,35,40,38)(2,6)(4,7)(13,21)(16,20)(18,24)(22,23)(25,27,31,29)(26,32,36,34)(28,35,37,38)(30,39,40,33)(2,6)(3,8)(9,11)(10,15)(12,17)(13,18)(14,19)(16,22)(20,23)(21,24)(25,28)(26,33)(27,35)(29,38)(30,32)(31,37)(34,40)(36,39) involution — undirected(1,3)(2,4)(5,8)(6,7)(9,12,14,10)(11,15,19,17)(13,20,21,16)(18,22,24,23)(25,29,31,27)(26,34,36,32)(28,35,37,38)(30,39,40,33)(1,4)(2,3)(5,7)(6,8)(9,13,14,21)(10,16,12,20)(11,18,19,24)(15,22,17,23)(25,30)(26,35)(27,33)(28,32)(29,39)(31,40)(34,37)(36,38)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.