You must have some kind of systematic study of God's Word.
This can be done in any number of ways. To begin, it is essential to read it through from cover to cover on a regular basis. Then, there should be a contextual study so that you know the theme of each book, the circumstances of each book and how Jesus is revealed in each book.
There are key verses that should be memorized in each book. I advocate that they be memorized first in the King James, because so much of the world uses the translation, and because there are many references that were written before the modern translations.
There should be prayer before study. Although the mind and emotions are surely satisfied by The Word, it is not an intellectual or emotional journey. You must be seeking a Person.
Soldier of The Cross, it is never old. It is never ineffective. It is never obsolete.
Get to know the Lord.