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