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