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