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