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