Renewing is easy. From the inventory screen, just click the green "refresh" looking icon on the left column. If it's not green, it's not ready for renewal yet.
Ads are currently eligible for renewal every 3-4 weeks depending on your plan level. When renewed, they jump to the front of some listings and are reshared in the MorphReport. Standard and Premium level members also have an auto-renew feature that will automatically renew as soon possible.
Starting this week, after an ad has been eligible for renewal for 75 days, we'll automatically expire it. In the future when when more sellers are familiar with this policy, we will shorten this period to a few weeks beyond the renewal period.
Finally, if your ad gets expired, it's just as easy to bring it back. Just click the green renewal icon.