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