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