Lemon Basil: How to Harvest, Store and Use

My sister just moved to a home and she has a garden. There are some existing plants that have been planted by the previous owner. She has this lemon-basil plant, we both love its smell.
1) How do we store it?
2) What can we use it for? Fish, poultry?
3) When is the best time to harvest it?

If the plant has not been recently planted this year then it probably is not lemon basil, but perhaps lemon balm. Both plants can be stored in the dried state, but lemon basil has to be dried very carefully in a shady airy spot so as to not turn it into tasteless hay! Freezing preserves the taste very well even if the colour tends to turn black.
Lemon basil is delightful with chicken and fish, and there is no reason not to try lemon balm for that use too. The latters more traditional uses are tea, and fresh in salads, soups and stews. It is medicinal as well and works well to heal herpes sores more quickly, calming the nerves and stimulating the heart.