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