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