how do I program a Keyless FOB remote for a 1997 Mazda Millenia

Hi, we recently purchased a 1997 Mazda Millenia and the keyless FOB remote did not come with it. (lost) We have access to another remote but need to know how to program it and where to find the keycodes on the car. Or do we even need keycodes. Is there just a way to program it without keycodes? Thanks to anyone who can help me out with this question.

How to set the keyless remote:

1) Sit in the driver's seat and leave the door open;

2) Find the door-light switch on the car at the bottom of the door opening; it's covered by black rubber and when the door closes, the interior and door lights go out; so when you push it with your hand, the same thing happens;

3) Insert key in the ignition and turn to on, back to off and remove the key;

4) Do this three times quickly (key in, key on, key off, key out);

5) Then push the door-light switch three times;

6) Push the lock button on the remote twice; the chime should ring;

7) Wait 10-20 seconds for several chimes and you're in business.
If you're programming more than one remote at the same time, repeat step #6 at the same time so all remotes have the same program.