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