In order to validate your diploma in the New York, United States, read this documents and feel free to contact their creator. Sergio Incera.
sergioincera@live.com
To sum up, you will required to fill some forms out for CGFNS, pay some fees and pass NCLEX exam besides TOELF or IELTS if you are form a country that does not have English as an official language.
The documents will be soon uploaded in English.