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