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