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