Here are just a few tips on buying and cleaning berries.
Select unbruised, heavy berries with red color going clear up the shoulders. Strawberries don't ripen after picking - they just rot. Less-ripe berries can be put to use in the freezer jam. Generally, one quarter of the less-ripe berries mixed with three quarters of the ripe berries make for a good jam.
Treat the strawberries gently. If they are not too soiled, just brush them off to remove dirt. If you need to wash them, use cool water and set them out to dry quickly.
Don't hull the berries until after cleaning - the water will just collect inside and accelerate spoiling. Here's a good trick for hulling strawberries: use a plastic drinking straw! Push the straw up through the bottom of the berry. It will force the white pith and hull out in one piece.
A colander will help keep air circulating, and moisture from collecting in the bottom, so the berries stay fresher. A nicer way to serve the whole berry is in a berry bowl. These are pretty ceramic bowls with large drainage holes and attached tray. Some even come with matching bowls and pitchers for sugar and cream.
An alternative would be to crumple some paper towels in the bottom of the bowl so that moisture is wicked away. Generally, don't wash or hull the berries until you are close to using them, and then enjoy these summer gems as soon as possible.