These tips apply to software development in any language:
The most reliable code is the code that isn't there. Keep
your systems small and simple.
Program code describes what you are doing. Add comments
to explain why you are doing it.
If you're writing a case statement it's very easy to
forget the EndCase or to write EndIf instead. Write the
skeleton of a code structure before filling it in.
Code should be as small and fast as necessary. No smaller. No
faster. Don't waste time on an ego trip making it better than
it needs to be.
Write an error handler first and make it log errors to a
disk file. Use error numbers so that your users can report a
number rather than having to read you the text of an error message.
Always write for multiple users and for many languages. The extra
features will not always be needed but you'll save time in the
long run.
Take a random walk through Help or the manual once in a while. You
will find lots of things that you had forgotten.
If you are going to make simplifying assumptions and take
short cuts - document them.
Design the structure before you write the code.
The first thing that you add to a program is a means of
stopping it. The Cancel button is the first control you
add to a form.