I came across these tips on MusicThinkTank for home/diy recordings and thought it'd be beneficial to most of you here:

1. Start with some good gear: A good microphone coupled with a good audio interface is the very foundation of a good recording. You don’t need a $1000 mic, but a decent microphone will do the job. The audio interface needs to have clear preamps and introduce minimal noise in the recordings. Your recording software needs to be good, so that there are no latency issues. Take some time to know your gear well before starting to record.

2. Correct recording formats: You need to decide in advance what recording formats you want to use. You can’t expect great results if you record at 8 bit, 8000 khz. The best format to use for recording is either wav or aiff. Use 44,100 Khz and 16 bit settings for best quality (this is the minimum setting. You can always go higher than this). It is always advisable NOT to record in mp3, as the format cannot capture the entire pristine spectrum of audio frequencies. But if you have to record in mp3, record at no less than 320 kpbs.

3. Mic placements: The mic has to be placed at the right distance from the mouth to capture the full sonic range of the audio. As a rule of the thumb, start with 9 inches of distance. Too near, and there are chances of capturing breaths and pops. Too far, and the vocal will sound boxy and weak. You also need to use a pop screen so that the breath and explosive “b” and “p” sounds can be filtered out. These pops and explosive sounds are very difficult to fix later on.

4. Levels and more levels: Make sure your recording levels stay in the green! This is very important, because if your audio starts clipping (the signal levels go above 0 db or in other words become red), you will get a nasty distortion in your recording, which sadly can’t be fixed later on. But, don’t keep the level too low, as that will result in more noise in the signal. A healthy -6db to -4db levels are good starting point. Keep a close eye on the levels throughout the recording session.

5. You can’t fix it later: Don’t leave your mistakes to be removed later in mixing and mastering. The later stages of post-production can polish your sound, but the results depend on the quality of the raw recordings. Good recording=good mixing and vice versa.

6. Noise-Your enemy: make sure you have switched off the fans and the air conditioner. Close all the doors and make sure your neighbor’s dog is not barking. Always record away from your computer, so that the cpu fan noise stays at the minimum. Always place the microphone on a stand. This will minimize any noise resulting from hand movements.

7. Stay in tune: always check the tuning of your instruments. Many instruments go out of tune during sessions and it’s important to re tune them. When singing, don’t have the mindset that the auto tune can fix everything. A good recording in perfect tune might take a few takes, but it is well worth it.

8. Record dry: it is best to record all vocals/ instruments without any audio effects. That way, you have more flexibility to play with during post production. Once you introduce an effect while recording, it becomes a permanent feature of the audio and can’t be removed later on. If you have to introduce some effects, try to keep them to the minimal

9. Train your mind and ears: your recording will be as a good as your ears. Listen to some great voice overs or commercial recordings. Compare your own with them. How do they sound when compared to yours? If you are not happy with how your audio sounds, then do some experiments with your gear and recording techniques, read some more great tutorials and learn. There are no short cuts to experience and knowledge.

10. Don’t be dejected: We all learn as we go. Your first recording won’t be Grammy winning, but it’s a good starting point. We all make lots of mistakes while recording, even for experienced artists and engineers. If you can’t get it right, don’t fret, do it the next day. Don’t be satisfied with mediocre results, always strive for excellence, and who knows, you might just win the Grammy! All the best for your recordings!

Source: 10 Great Tips For Home & DIY-Recordings - MTT - Music Think Tank
Another good tip shared in the comments was to keep your hard drive organized! That doesn't only apply to recording.

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