Step 1:
Complete the tutorial on Moving From One Activity to Another First. Link

Step 2:
Edit the nextAcvitiy method to pass out data.

//In MainActivity.java
public void nextActivity(View view){
    //Create the intent object to pass to another activity
    Intent intent = new Intent(this, MainActivity2Activity.class);

    //Add information to the intent object
    //The first parameter is the identifier string.
    //The second parameter is the data itself. Look into
    //the documentation for the Intent object for the
    //types of data that can be passed.
    intent.putExtra("myText1", "Hello");  //Storing a String
    intent.putExtra("myNum1", 555);    //Storing an int

    //move another activity given by the intent object
    startActivity(intent);
}

Step 3:
In the other activity, MainActivity2Activity, we will display message passed in.  We will edit the onCreate method to receive the intent and display the data.

//In MainActivity2Activity.java
@Override
protected void onCreate(Bundle savedInstanceState) {
    super.onCreate(savedInstanceState);
    setContentView(R.layout.activity_main_activity2);

    //Receive the intent object
    Intent intent = getIntent();

    //Getting the data passed in from the intent.

    //Put in the identifier string in the getStringExtra method
    String passedMessage = intent.getStringExtra("myText1");

    //Put in the identifier string and default number
    int passedNumber = intent.getIntExtra("myNum1",0);

    //Display the results
    Context context = getApplicationContext();
    CharSequence text = "text: " + passedMessage + "\nnumber:" + passedNumber;

    Toast toast = Toast.makeText(context, text, Toast.LENGTH_SHORT);
    toast.show();
}

Step 4:
Run the code. Click the button in MainActivity. You should see..