Determine the reed strength that works best for you. Reeds range from a strength of No. 1 to No. 5. No. 1 reeds are the softest and require the least amount of air pressure to vibrate. No. 5 reeds are the hardest and will require the most air pressure to vibrate. Purchase one reed from each strength by the same brand to determine what level reed you should use.
Purchase several reeds from different manufacturers and try playing on each reed for 30 minutes. Take a rest. Narrow down your reeds until you have found a reed that is comfortable. Look for a reed that responds well to your embouchure, is comfortable to play on and has a consistent tone throughout the range.
Place your reed in a glass of water for five minutes a day for four days to help break in and moisturize the reed.
Fix a reed that doesn't have a smooth bottom by taking a razor blade and scraping lightly along the bottom of the reed until it is smooth and flat.
Modify the strength of the reed if you find that you aren't quite comfortable with two adjacent strength levels. Choose the stronger version of the reed and clip the end of the reed, using a reed trimmer.
Sand the reed, using 250-grit sandpaper if you find that the reed feels harsh.