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