|Image from Scenic Reflections.|
If your strawberries live in garden beds, simply cover them up with a few inches of straw or leaves for the winter. Wait until the ground is fully cooled off and your plants are done growing for the year. Then give them a nice, thick layer of mulch. This does double duty; protecting the fruits from frigid winters, and providing great compost material for your soil. Be sure to check on the plants a few times over the winter to make sure freezing and thawing hasn't forced them up. If so, tamp them back down, water, and add more straw or leaves.
Strawberries that are growing in pots should be placed somewhere cold but not frozen. An unheated garage is a great place to store the fruits for the winter, but you'll need some sort of insulation to ensure your strawberry plants don't freeze solid. Don't worry about the lack of light, as the strawberry plants will be dormant and won't need any light. Just be sure to add water every few weeks to ensure the roots don't dry out. You can also plant your strawberries in the ground for the winter, utilizing the straw-as-insulation approach outlined above.
One of the best ways is to over-winter container strawberries is to put the pot in a larger container and insulate the space between with leaves or straw. Or, place the container on the ground next to a heated wall and ideally out of the winter wind. Insulate the exposed sides of the container with mulch, leaves or straw. Or just bury the container. The surrounding soil will insulate the roots over winter. Then dig up and hose down the container next spring.
Please don't try taking your strawberries inside to continue growing as houseplants! Strawberries need a dormant season in order to trigger a new round of growth in the spring for fruiting.