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