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