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