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