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