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