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