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