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