1. Saturate yourself with the Word of God, the Bible. There is no reason to think that God will ignite the powder of His Spirit if you don’t load your cannon with the bullet of the Word. Acts 1:8 and Luke 24:48 teach that the power is given for effective witness of Jesus and His miraculous power. And you witness primarily with the Word of God, as it speaks about the person and redemptive work of Jesus Christ.
2. Believe what the Word of God says. If you don’t believe the Word, you wont have the power of the Word.
3. Pray earnestly for it and fast. In Acts 1:13, the disciples devoted themselves to prayer while in Jerusalem waiting for Pentecost, “All these with one accord devoted themselves to prayer.” Also, this is what the disciples were doing in Acts 4:24–31 when they were all filled with the Holy Spirit and spoke the Word with boldness. They were praying. And they were praying the Word of God.
4. Submit to the Holy Spirit. Sometimes you have resisted the Holy Spirit so often when He is calling you to bear witness to Christ you are unfit for the flow of His power. The channels have become so clogged with fear and doubt and worldliness that what you allow through is a barely visible trickle of obedience. God’s power is a waterfall and will flow torrentially if you obey His Spirit.