(Best months for growing Garlic in USA - Zone 5a regions)
P = Plant cloves
Garlic is traditionally planted in cold weather and harvest in summer ("plant on the shortest day, harvest on the longest"). Plant the cloves (separated from the bulb), point upwards, deep enough to just cover with soil. A fairly tough and easy-growing plant. On better soil with regular watering you will get a better crop. On poorer soil, and forgetting to water them, you will still get some garlic, only not quite so much.
Leave a garlic to go to seed, and you will probably get plenty of self-sown plants the following year.
To keep for later use, dig up and leave to dry out for a day or so after the green shoots die down. To use immediately, pull up a head when you need it, or cut and use the green shoots.
Cut the growing shoots or use the entire young garlic plants as 'garlic greens' in stirfry.
We cannot help if you are overrun by giant slugs.