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