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