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