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