Learn Finnish: Tämä on tottumus, joka helpottaa elämääni.

In Finnish, the pronouns for the first and second person (like minun and sinun) can usually be dropped if you attach a possessive suffix to the noun. Because elämääni has the first-person suffix -ni at the end, the word minun is optional and is often left out to sound more natural.

Why is the word for life in the partitive case (elämää) before the suffix is added?

The verb helpottaa (to ease or make easier) is a partitive verb. It requires its object to be in the partitive case because easing something is treated as an ongoing or partial action. So, elämä becomes elämää before we add the -ni suffix.

In elämääni, which comes first: the case ending or the possessive suffix?

The case ending always comes first. You start with the noun elämä, add the partitive ending -ä to get elämää, and finally attach the possessive suffix -ni to the very end.

Why is the relative pronoun joka used here instead of mikä?

You use joka because it refers back to one specific noun right before it, which is tottumus (habit). You would use mikä if you were referring back to an entire preceding sentence, a superlative, or a pronoun like kaikki (everything).