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