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