How to best charge the battery?

You should recharge it to full charge regularly, before it has an opportunity to fully discharge.

I have read it is best to not let your battery fully die, but is it better to charge it everynight while it has over 1/2 battery life left, or to charge it every 3rd day or every other day when it is at 1/3 or 1/4 battery left?

thanks in advance.