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