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