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