"How do you do it"?
A quality performance isn't worth much if it isn't captured on quality equipment. Here's what I use.
Tools of The Trade
Acoustically Treated Environment
Microphone
Interface
This is where the magic happens. My isolated recording space has been acoustically treated to maximize the quality of the sound inside. No matter what I record, I always get a clean, crisp, listenable sound.
Any voice artist will tell you that a good microphone should capture every nuance in your performance, myself included. That's why the Neumann TLM 103 is one of my favorite mics to work with. Quality microphones don't come cheap, but they are vital to a quality recording.
Don't let it's size fool you. My SSL2 is instrumental in getting my voice into the computer. An interface can make or break a recording. SSL's exceptional preamps guarantee that it's one of the "makers".