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