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