You can reactivate your LivingSocial Plus membership at any time. First, just log in to your account at LivingSocial.com. Click on your name in the upper right-hand corner and select 'My Account' from the drop-down.
If you've ever been a member of LivingSocial Plus, you will see a box with an option to 'Restart Membership.' Click on that link, confirm your credit card, and you're back in business!
For more information on LivingSocial Plus and what is included in your membership, check out our help site article: What is LivingSocial Plus?