Shoshana’s advice is most consistent with my experience and reading about cats, and I’ve had one or two cats as a member of my household for my entire life.
Neuter your pet: The most humane thing you can do, regardless. And the bit about smaller territory applies to both neutered male and females. Neuter your pet early at 5 or 6 months, before he or she gets into a spraying habit.
Gradual access: Supervise your cat outside at first, and the first few times, limit the outing to just a couple minutes. Establish a boundary ahead of time, and don’t let your pet cross it. Start with just a patio or small patch of lawn. Expand this territory gradually. Don’t let the pet wander out of sight of your door until he/she learns the lay of the yard and knows which entrance belongs to you. Keep your pet between you and the door, so in case it begins to exceed your preset boundary, you can scare it back inside
In fact, I began to startle my cats the first time in a new yard to try and see what they would do. If they don’t run for the door they came out of, then it’s not time to expand their “run.”
Eventually your cat will be able to go outside unsupervised. It will establish a “beat,” to patrol the boundaries of it’s territory. It may still get into fights or standoffs in order to defend its borders. This is normal, healthy cat behavior.
But, you expose your cat to additional risks. Fleas and other parasites - so use Advantage flea control treatments monthly. Keep the vaccinations up to date. Annual checkups. Examine the cat regularly for scrapes and bruises, especially after fights.
If you live in an area with coyotes or other hunting animals, make sure your cat has a safe place it can retreat to, either a tree or a small outbuilding or somehting similar.
Feed your cat on a regular schedule. Do not leave food outdoors for your pet. Require it to come indoors to be fed.
Make sure your pet wears a collar with an ID tag, including your phone number.
If you can, teach your pet to respect motor vehicles. Scare it with your car in the driveway. Too many cats do not have the proper fear of cars.