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