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