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