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