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