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