The simple answer to this question starts with finding a good piano in a good auditorium.
By 'good piano', I mean a Steinway, Bechstein, Bluthner or Bosendorfer grand piano. Yamaha make good grand pianos too, but they don't have quite the same reputation. There are plenty of such pianos around – you don't need to compromise.
By 'good piano', I also mean one that is well set up and well in tune. Concert pianists have pianos set up to their own liking, but it will be easier just to find one you like. It should be tuned specifically for the recording.
By 'good auditorium', I mean one in which the piano sounds good to the ear. It should sound good when someone else is playing it. You can't judge what its potential will be for a recording if you are playing it yourself. Firstly, you are distracted by playing. Secondly, you're in the wrong place!
Next, you hire a recording engineer who is experienced in recording the piano. Judge this by the CD's of his or her work he or she can show you.
If this is the first time you have made a serious recording, you will need to do some tests at home. Use a simple cassette dictation machine (ordinary cassettes, not the small ones). Anything more complex than this will detract from the quality of the tests.
What you are testing here is your ability to play to your satisfaction. You could go to the next level and engage a producer (perhaps a musician friend) to help you judge objectively. The standard required for a successful recording is a lot higher (and different) than for a concert.
You need to be absolutely sure that you have fine-tuned your skills, otherwise you will be disappointed with your finished recording.
You should book a minimum of a four and a half hour period in the auditorium, with three hours of recording time for the engineer (plus an hour to set up, half an hour to take down, or whatever the engineer recommends). In this time, you should aim to complete no more than around twenty minutes of music. This is how much professionals record in a session.
The session will start with a rehearsal for you, and setting of mic positions for the engineer. Mic setting is done by a combination of experience and experiment. You should expect this to take some time. When the engineer seems satisfied, you can listen to playbacks. You have to make sure that the sound is as you want it to be. It cannot be changed, other than by electronic means, later.
Once you are ready to record, you should aim to capture a complete performance of your first piece, whether or not there are a few mistakes. Take care to budget your time carefully. It will disappear quicker than you think.
When you have a good take, listen to a playback and decide which areas need attention. List them on paper carefully, and return to the piano to re-record these sections – plus lead-ins and lead-outs that help make you feel comfortable, and can be used for editing later. These are in addition to your complete take.
Make absolutely sure that a) you have recorded all the music, and b) that all mistakes or gray patches have been covered.
You should spend time listening to playbacks. This is not time wasted – it is an important part of the process of the session.
By the end of the session, you should have decided which takes you are going to use and approximately where edits need to be made. The engineer will decide on precise edit points according to technical matters.
And, apart from waiting for the engineer to return to you a CD of your playing, that is it! In principle it's straightforward. In practice there is a learning curve. Naturally you try to make your first attempt as good as possible, but there will inevitably be room for improvement in second and subsequent sessions.
Good luck! And don't forget to send a copy to Audio Masterclass!
By the way. You may want to consult 'How to make a CD of an acoustic piano (the hard way)', but I suggest you don't bother!