How to create a logging system for a system that serves users?

I have a system (in NODE.JS) that servers users (around 10000 users) and I want to write to the database every step that they do.

For example:

1.When a user logs in / logs out - write to the DB

2.When user changed his profile - also

3.User made some kind of transaction ... etc

I don't want to add a database action to every action that the user does , since it takes more process time and on a larger scale there might be delays.

What would be the best approach to write to the DB every step without too much delays ?