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