How do we gain marifat (knowing) of Allah swt exactly? How to become sinless or reduce sin so much that it is only done on occasion? How to come to love Allah swt?

This is an excellent question. Knowing God involves doing the following:

1. Know yourself in the sense that you know your weak points and trying to work on it.
2. Understand the teachings of Qur’an and try to implement the teachings. Read few verses of the Quran daily and reflect on them
3. Befriend and associate with people who always remind you of your duty to Allah.
4. Take care of your daily prayers, it’s timing etc
5. Be discipline – meaning do what you know it’s right and try to stay from what’s wrong.

Doing the above will not only help you know Allah but make it easy for you to stay away from sins