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