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