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