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