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