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