1. Read your lease. No, seriously read it. It won't be the most exciting night table material but you'll thank yourself when you do read it. A lease is a binding legal contract. It creates a binding relationship between you and your landlord. What are you agreeing to? If you don't understand, ask questions before you sign it.
2. If you don't know if it's allowed, get permission. "These rooms could use a fresh coat of paint in a new, exciting color." "Hey, we should get a puppy!" "Let's replace the light fixtures in the dining room." These all seem like tasteful upgrade, so clearly they are improvements to the place. Get the landlord's written permission first. If the lease says "DON'T," you must get the exception in writing (not a verbal, not a handshake - in writing) to make it a "DO." Save the signed letter and keep it in a file. You'll need it later when you move out and your landlord has forgotten.
3. Put it in writing. If you have a non-emergency request such as a leaky faucet, submit the maintenance request to the landlord in writing. You can also follow up with a phone call. You can write a note to the landlord and submit it with your rent check. Or, you can fax or email the request as well. While landlords appreciate being notified of maintenance issues right away, keep in mind there are some small issues you need to take care of yourself. For example, if a light bulb goes out or the smoke detector needs a replacement battery - grab a step stool and swap it out on your own. No need to bother the landlord.
4. Treat 'em how you want to be treated. Be a respectful and courteous neighbor and tenant. Landlords don't like mediating arguments between tenants. Many of these issues can be resolved without involving the landlord. If you have problems with a neighbor, don't be passive-aggressive. Address the problem directly with the offending neighbor. The goal is not to argue or prove your point, but to create an environment where both parties can live peacefully.
5. Respect your home. Keep your house in clean and sanitary condition. If you have pets, pick up after them (inside and outside).
6. Pay your rent on time. Many tenants believe they have a "grace" period. Most leases will not charge a late fee until three to five days after the due date. Though this appears to create a grace period, it does not. If you pay rent three days late every month, you may never incur a late fee. However, when you move out and you need your landlord's reference, h e can state you were late every month on rent. Make sure to get your rent in on time.