Catching Exceptions

How would I go about catching this error before it got to the when others clause? I KNOW I NEED TO WRAP THE INNER BLOCK WITH A BEGIN AND END BUT I THINK I AM PUTTIN ONE OF THE BEGIN IN THE WRONG PLACE

Using oracle

CREATE OR REPLACE PROCEDURE example1 

(
  p_first_name IN varchar2)

as
    v_test_variable varchar(4) := p_first_name;
BEGIN
 BEGIN
  DBMS_OUTPUT.PUT_LINE('Exception Propagation Example 1');
 EXCEPTION
 when others then
  DBMS_OUTPUT.PUT_LINE('An error occured in the declaration section ');
END ;


EXCEPTION
    WHEN value_error THEN
    DBMS_OUTPUT.PUT_LINE('You cant put ['||V_TEST_VARIABLE || '] in a 4 character string.');
END example1;
/
show errors
    EXEC EXAMPLE1('hello')