It's often used as a response to a question or statement, implying that there is nothing significant or noteworthy to report.
Here are some examples of how it might be used:
* "Did you see the new movie?" "Nada amiga, I haven't had time."
* "What are you doing tonight?" "Nada amiga, just staying in."
* "How was your day?" "Nada amiga, just another day."
The "amiga" part is a friendly way to address a female friend. You could also use "amigo" to address a male friend.