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