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