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