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