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