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