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