Question

how does portia plan to guide yong german to the wrong casket? in act 1 in merchant of Venice

Answer 1

Because she loved Bassanio and did not wanted anyone to choose right casket...

Answer 2

To prevent the young German from choosing the right casket, Portia instructed Nerissa to place a tall goblet of Rhenish wine on the wrong casket. Portia was sure that the German suitor will not be able to resist the temptation of his national drink even if the picture of the devil himself was within.