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