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