Purchase or harvest fresh basil at its peak. Select firm stems with full foliage that shows no signs of wilt. Sniff the herb before purchasing or picking, and only choose those that have a strong, pleasant aroma. Basil at its peak stores better and retains its flavor longer.
Hold a bundle of basil stems together, with the leaves all at one end. Rinse the herbs under a light trickle of cool water.
Shake the excess moisture from the foliage. Lay the bunch on top of a paper towel. Pat the top of the bunch dry gently with a second paper towel.
Fill a small glass with two inches of water. Using kitchen shears, cut the bottom of the basil stems at a 45 degree angle and stand them up in the glass of water.
Place a clear plastic bag over the top of the herbs and glass so that it loosely covers the basil but still allows for some air circulation. Set the glass inside your refrigerator. Use the fresh basil within seven days.