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