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