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