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