Every newly enrolled account automatically gets enough pending vote balance for their first $0.02 upvote. After that, your pending vote balance gradually recharges based on your subscription level. Whenever your pending vote balance is high enough to support another upvote, it will be delivered automatically on your next post.

Since only 1/3 of pending vote balance is delivered on any post (to smooth voting distribution and reduce abuse), your pending vote balance will need to reach $0.06 for your next upvote. How long this takes depends on your subscription level and on HIVE price and reward pool behavior.