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