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