Essentials to have on hand for kitty:
1) Litter tray with a supply of non-clumping litter.
2) Kitten food
3) Food and water bowls
4) Cat bedding
5) Cat toys and something for your kitten to snuggle
6) Scratching post or scratching pad
Again, a simple, inexpensive litter pan or even an old large-sized baking pan will work rather than buy anything fancy or pricey. What is most important is keeping the litter clean by daily scooping of the cat poop and frequently emptying the used litter, washing the tray with soap and hot water, then putting in clean fresh litter. Don't let the litter stay soggy. If it's soggy, it needs changing! By the way, rather than buy an expensive plastic scoop for sifting poop out of the litter, just get a really cheap, big, slotted metal spoon from the discount store. It will work just as well and last much longer.
Start your kitten eating the same food it has been getting and then gradually transition to whatever food your vet says is best. Too sudden a change will give the kitty an upset stomach, nasty poop and maybe throwing up. All things in moderation!
Food and water bowls should NOT be plastic. Those tend to create skin problems on cats chins. You need glass or metal bowls. In the past we've used glass ash trays as food dishes. It is important you keep plenty of clean, fresh water available for your kitty, preferably in a bowl that cannot easily be tipped over. Be sure not only to change the water every day but to also regularly wash the bowl. Same with the food dishes. Don't put food in a dirty bowl. It not only is better for kitty to have clean dishes, it will be nicer for you too to avoid smelly dishes that might attract insects. Again, simple glass or metal bowls from a discount store work well. You don't have to buy something labeled as a pet bowl.
For cat bedding, if you don't have a couple of old towels or a small blanket go buy two or three of the least expensive towels you can find. It's good to have more than one so that you can put down a clean one while a dirty one is in the laundry.
If you get a young kitten, having a small stuffed animal for it to snuggle makes kitty feel more secure. Remember, your kitten will be used to snuggling tightly with litter mates and the momma kitty and will feel insecure sleeping without something similar to snuggle. Again, you need not get anything expensive; a very simple stuffed toy will do, nor does it need be a new toy. Just make sure it doesn't have little pieces such as glued eyes or string whiskers your kitty can easily chew off and swallow. And a tied up sock, with or without catnip to wrestle with, a crumpled piece of paper to bat around and chase, those sorts of toys. Not too many though. A few will do. What is more important will be you taking time to play and interact with your kitty.
It's easy to spend a fortune on fancy scratching posts but your kitten will do fine with a simple one that isn't expensive. It's more important how you go about teaching kitty its scratching manners than what type scratching post or pad you get.
As to the droppings and wetting in the tray, yes they will be somewhat smelly. However, if you make a constant habit of scooping out all the droppings every morning and again every evening, in fact whenever you find droppings in the tray, and to stir up the litter well to keep the bottom layer from getting all soggy, it shouldn't be much of a problem. There will be times when you have to cope with some smell and having to air out the room where the tray is kept after kitty has left some droppings in the litter. It's a bit like having to cope with diaper changes on a baby. Regular changes of the litter before it gets soggy and stinky not only will be more pleasant for you, it is better for your kitty.
Depending on available space and what your parents' say, you might put the litter tray in the bathroom. For the first few days and nights, you can keep your kitty in there at night and when you aren't home. Once kitty learns to be well housebroken, then you can leave the door open and let kitty roam the house. Another place for a litter tray is in a laundry or mud room. You can also put it in your room. Wherever you put the litter tray, keeping the droppings scooped out twice a day and changing the litter regularly is what is most important.
Don't try to have a new kitten spend the whole night in a room away from the litter tray. To teach it to be housebroken, it needs to be near the litter. So don't expect to snuggle kitty all night long at first. Kittens, like small children, often need to be reminded and encouraged to go to potty. Always be gentle, positive, and give your kitty praise when you show it the tray and when it uses the tray. Positive reinforcement!
Wherever kitty spends time confined, whether with you in your room at night and while you are at school, or any other time, be sure always to have a bowl of water available along with access to the litter tray. You don't have to keep food available all the time. It's okay to feed kitty a couple of times each day on a regular schedule and pick up the food dish after kitty finishes each meal. Again, let your vet give you guidance on what food to feed, how much, how often.
Your kitty can sleep on your bed without a problem unless you prefer not to have kitty on the bed. It is fairly easy to teach them to stay off your pillow and sleep farther down the bed. That's a good idea. Young kittens will tend to want to wake up and play, play, play in the middle of the night. Cats are naturally nocturnal hunters. Don't punish your kitty for that but neither do you need let it be a problem. If kitty wakes you up wanting to play in the night, gently but firmly place it where you want it to stay and stroke it as if you are the momma cat licking down her kitten. Then give the kitty no other attention. It will learn that it can't get you to play by waking you up. However, be prepared for your kitty to amuse itself some at all hours by playing with a toy, exploring, and generally being a cat.
I'm sure others here at TDK will have lots of other good advice to give and think of things to mention I've overlooked. If you haven't already done so, make a point of talking with family, friends, neighbors who already have cats and learn from them what it's like having a cat. Not everyone handles the details of cat care the same depending on circumstances, knowledge, and creative thinking. I got my first cat as a very young girl almost 50 years ago and I'm still learning new things about cat care!
Again, you're asking all the right questions and obviously thinking this through ahead of time. You'll do fine. As will whatever kitten ends up choosing you! :-)
