What are the best righteous deeds after the obligatory ones?

The best deeds after the obligatory acts vary according to individuals and times, but there is a consensus among scholars that constant remembrance of Allah is the best occupation for a servant, based on the hadiths of Abu Hurayrah and Abu Darda. The minimum of this is adhering to the established supplications from the Prophet, peace and blessings be upon him, then adhering to remembrance (dhikr) generally, the best of which is "La ilaha illa Allah" (there is no god but Allah), though some other forms of remembrance might be better in specific circumstances. Everything that brings one closer to Allah, such as seeking and teaching knowledge, enjoining good and forbidding evil, is considered a form of remembrance of Allah. If one is unsure, they should perform Istikhara (prayer for guidance) and supplication, for it is the key to all good, and they should seek out the virtuous times for supplication.