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