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