What do you use to make your home smell good?

As someone who doesn't use these, the first things I think when I enter a home with them are:

This smells nauseatingly, overwhelmingly artificial.
This can't be healthy (spoiler: correct).
I wonder what they're masking to want to spend money on these things.
I would prefer to be outside right now.

OP, as the other comment said, keeping a relatively neutral smell hopefully is a good goal and then maybe add pleasant undertones later. Instead of trying to introduce positive smells (cook at home more often or grow some plants, and you'll get a bit of that!):

Make sure dirty laundry is kept in a hamper with a lid and washed at regular intervals.
If you have pets, make sure they're housetrained and that accidents are cleaned – preferably with an enzymatic cleaner. Bathe your pets regularly too. If you have small animals in an enclosure, keep that clean.
Shower regularly, and clean your bedsheets regularly.
Make sure the house isn't excessively humid.
Vacuum at least periodically.
Make sure dirty dishes don't just sit dirty out in the open for long periods.
Make sure smelly garbage has a lid over it and is taken out routinely, especially if there's stuff like meat scraps in it.
Open the windows on nice days when it's around room temperature.
If it's especially bad for some reason, an air purifier may help.
Regularly clean your bathroom.
Keep your fridge organized so food is less likely to go bad (or bad food gets caught quickly).
If you have a shoe rack near the door and you want to be really extra, you can once in a while deodorize your shoes. Maybe I'm a freak that I don't do this.
Make sure the house isn't excessively cluttered.

This isn't all-or-nothing: any of these will help with the odor, and that's the goal.

Adding that dust traps odours. Pays to wipe down horizontal surfaces and objects regularly along with walls and such.
I violently agree with the first part, I HATE air fresheners with a passion.
That said, I'm extremely lax about many of the other things but have no problems with the house getting stinky (though I don't have pets, and am rigorous about not having smelly kitchen garbage, and as it is an older house is not air tight and so air does get in and out).
My laundry and shoes do not smell. Maybe I'm just lucky biochemically, but the same thinking / influences that lead people to think they need air fresheners can lead them to fuck up their skin biomes with harsh cleaners (especially anti-microbials), deodorants, and other unecessary "product" may actually lead to a greater tendency to be smelly. Houses have biomes as well and the same may apply. Unless you are immunocompromised or running an operating theatre you do NOT need antimicrobial anything.
If you sweat something up, change it right away and hang it to dry, and it should not get smelly. Do not put it wet into a closed hamper, or it WILL get smelly.

I use nothing, I don’t feel like fighting a never ending battle. But maybe you could try getting some flowering plants around your house to give it a floral scent

Cooking and cleaning mostly.

Clean regularly.

nothing. We clean the place and we open windows as often as possible (even during winter cold).

What do you use to make your home smell good?

Windows. I can open mine.

Like putting on cologne or perfume and failing to mask body odour. You have to actually clean, not spray carcinogenic scents on the mess that briefly mask it. It's usually fabric like bed sheets and couches, carpeted surfaces, human/animal dander and oils. Garbage cans with poor seals. Poor choices in cat litter systems. Stuff like that.

Then open windows for air circulation. If you can set your furnace fan (if you have one) to always run even when not heating that also helps redistribute stale air.

Beyond that just give up and go nose blind.

Edit: ceiling fans are great too.

Depends on how much money you want to spend. People here giving pointers on cleaning sources of smells and I second that, but to answer your question, three things work for me to actually make my home smell like something in particular:

1- Essential oil diffuser. IMO the most effective, the downside is that not all essential oils are as fancy as, say, the fragrances of the other options in this list. Also you have a bit of an investment upfront, diffuser+oils. But they last reasonably long.

2- Reed diffusers: vast variety of prices here, the pricier ones are nicer and last longer. The downside is that the scent will lose effectiveness with time. Usually I can't smell the oil once it's reaching a quarter left unless I pick a reed and smell the oily end. YMMV depending on how large and how ventilated the area is.

3- Scented candles: again, you get what you pay for. Honestly it's usually the big very expensive ones the only ones that really work. Also, fire, so that's a potential hazard if you have pets/kids. IMO they can work if they're good, but they don't last as long, meaning, more expensive.

So yes I hope this helps. Good luck

Feel like reed based lasts longer as it's applied during a longer duration.
The smell from diffusors is mostly gone as soon as the oil is used up.

The main thing I recommend is having house plants. They will filter out things in the air and will add additional oxygen which to our noises make things smell cleaner. I would also recommend cleaning more often especially your floors. We use Florida water whenever we clean our floors which lingers in in the air for days. We also leave bounce sheets under our garbage bag in our closed garbage can it captures the main source of bad odors for a house. We also use incense sticks in our bedroom which smells great. In the winter when the house gets very stinky and stale we like to set up a simmer pot. Its basically just a boiling pot filled with good smelling spices, fruits, and / or spices. It also humidifies the house which is great.

Steam machine for cleaning, airfilters always open, climate/humidity control, no smoking.

I don't use scented stuff, it is bad for your health breathing in all these chemicals. With scented candles and incense, burned chemicals. My wife was into the diffuser stuff and all, but stopped after a few days because I had increased asthma attacks.

Weed

Whenever I cook, the house smells amazing for a few days. Last was 2 batches of banana bread!

Regular airing.

Besides that I like to use some ultrasonic water vapour diffusor with essential oils.
Sadly the smell doesnt linger as long.

Incense. Lavender mostly, helps keep away certain insects too

I love incense, although I once had a neighbor and smoking buddy tell me that my place smelled like "a French whorehouse."

I keep my house very clean, and when the weather allows I open windows to let in fresh air. I also have reed diffusers throughout my house to add a little scent. IMO the key is to choose one scent for your whole house so that it smells cohesive, and to choose a scent that is mild, not too artificial or overwhelming. Right now I've got the Life in Lilac diffusers in Peppermint Bliss and they smell great. All I have to do is flip the reeds once a week.

You might also be going nose blind to the febreze plug-ins if the scent is disappearing after a couple of days.

Used coffee grinds.

I often clean and place aromatic oils in the rooms + live plants.

Soap, particularly the one made for washing floors. It has a very discreet smell and doesn't linger too much. I also have quite a small bathroom so I hang laundry to dry in most other rooms.

I mostly prefer my home smelling "clean" rather than perfumed, but I have on occasion used those sticks in containers with perfumed oil, but with only one or two sticks (the fragrance can be really overpowering when using all the sticks, and the oil will last longer with fewer sticks in it) - maybe try that? It will last a few weeks at least.

Still...3-4 days sound very short for a plugin. It might be that you get used to the smell after a few days? Most of us become nose-blind to our own homes. Ask someone else to visit and tell you if they can smell it once you think the fragrance is gone.

Candles, preferably. I am cleaning constantly, but I've always had an overly sensitive nose so I sometimes need something stronger if there is a smell I can't get rid of.