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