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