I've always owned a cat, but the destiny of a human is to outlive his cat, which means I've had many. My current cat, after a campaign of complaining, managed to perch himself on my lap even as I type this. He is what I call an affectionate type of cat, which is the best kind of cat to have. He looks to me as an adoptive parent, although he's old enough not to go clawing for teats, for which I'm thankful.
The first secret to having a good cat is picking the right one from the animal shelter, the one that likes humans to begin with, and isn't too shy. Some cats are cat-racists who prefer to stay by themselves or by other cats all day. They are by nature not fond of human company. I don't want a rambunctious cat either, one that is going to tear up the upholstery. I just want a smart, friendly extrovert. This is my ideal. However, to each his own. Some people may prefer a different type of cat.
People think that the first priority of a cat is food, however, when I feed the two cats I own, one cat will stand around watching me and craving attention until I leave the room, whereas the other cat dives into the food.
My policy is to have an all-day kitty buffet, where I fill a large bowl. The bowl is placed in the garage upon a table, so that it has some protection against ants and insects. If it is ever empty, I fill it. The cats can eat as much as they like. After all, I enjoy an all-day human buffet. My cat and I both follow the same rule. When hungry, eat.
You may be able to keep your cat outdoors, but be mindful of the many cat diseases raging out in the world. I buried my last cat, an outdoor cat who succumbed to feline HIV and leukemia contracted from neighbors' cats. If in your location you have many cats wandering through your yard, then it may not be safe to let your cat outdoors. Wandering cats tend to fight, and fights bring infection. Worse are cars. I remember driving to work one day when I spotted one of my cats dead on the road. I suspect that some drivers go out of their way to kill a cat, or at least don't bother braking. There is not a high enough premium put upon life in the world today. Some guys think that it makes them more of a man if they kill an animal. You may not know how risky your location is until you bury a cat.
Cats are easy to train to use a litter box. That is the one area where they learn with rapidity. When starting potty-training, you can teach your cat not to mess outside the box by showing the cat the mess, saying "No" in a loud voice, and holding it while you clean the mess up. It should only be necessary to do this once or twice, at the most. Anymore, and you must be doing something wrong; making the cat think that he is being rewarded, for instance.
If, after a successful career in using the litter box, a cat stops using it and messes in the wrong place, then that is a sign of stress. You should not punish the cat, but instead address what is wrong with it. The most common problem is a litter box that is overfull. Cats do have standards. If the litter box is too nasty, they will not want to enter it. There is also the case of indigestion. If the food is making the cat sick, switch brands. Compost the bad food in the backyard. It is better to pay a little extra on cat food, rather than have a sick cat. I like the major brands over the cheapo brands which I have found make my cat sick to his stomach. I am not sure what they are putting in those cat foods, but some of the brands smell bad even before digestion.
Keep a collar on the cat at all times with a metal tag engraved with the cat's name and address, for the event when the cat escapes to the outside, which will happen, because the cat is faster and stealthier than you are. You will open the door many times, and the cat will be watching and waiting for his chance of escape each time. Nature calls him to explore the outdoors, although there are hazards waiting for the cat outside. The best and the cheapest collars and engraved tags can be found on E-bay. They are so cheap, it is ridiculous, and I don't see how the sellers make a profit. I prefer my cat's collar to be studded with gemstones or rhinestones to denote high prestige, a valued pet beloved by its owner. This gives it some protection against maltreatment, should he come into contact with strange humans. Not all humans agree that pets deserve to be treated well. There are angry people in the world that want to take out their anger on an animal. At least with the identifying tag, notice is served that a human protector may be displeased by any mistreatment. A cat with no collar and no identifying information may wind up in the animal shelter, and from there, the grave.
Flea collars don't work well, in my experience. They reduce, but do not eliminate fleas. To address the flea problem, I bought the excellent brand-name flea-killers that protect for thirty to forty days at a time. Four consecutive months of usage may suffice to protect the cat year-round, if kept indoors in a small house. I stop the treatment in winter, and resume in the Spring. This is both to save money and reduce the cat's exposure to whatever chemicals are in the insecticide.
It is important to treat the cat like a valued member of the family, if you want to have an affectionate and vibrant creature. Let it play, let it wander, let it explore. Encourage play with toys. A cat can benefit from having at least one cat companion, another cat to play with and be pals with. My cat has his brother for company. The brother is more of a reclusive type, although he can be affectionate in his own way and if the mood strikes him. They cooperate to a surprising extent. However, the brother is fonder of my partner than me. Cats do have their preferences. One cat prefers my partner, whereas the other cat prefers me. So we each have our own cat.
Listen to your cat, because it does have thoughts that it wishes to share. Lacking the power of the human voice, a cat requires a receptive audience in order to communicate. This means you must watch its facial expression and body language and listen to any sounds it makes to learn its will. In time, you may become adept at reading your cat.