The key to effective prayer is knowing to whom you are praying and having access to Him. Then, pray. And pray some more.
What makes for effective prayer?
We often think of "effective prayer" as prayer that leads to the results we desire. But prayer is not some incantation or formula to produce "results." Rather, prayer is a means of communication with God. It is a privilege that He grants us and the means by which He often chooses to work. There is no doubt that God commands us to pray and that prayer is effective. The results of prayer are not only in the things we see God do in response to prayer, but also in the deepening of our relationship with God. So how can we pray effectively?
First, we must know God. A relationship with God is available only through His Son, Jesus Christ (John 14:6). When we put our faith in Jesus as the perfect God-Man who lived a life without sin, died on the cross as payment for our sins, and rose again victorious over sin and death, we are forgiven of our sins (John 3:16–18; Ephesians 2:8–10). God applies Christ's righteousness to us and we become God's children (John 1:12; 2 Corinthians 5:21).
The Old Testament sacrificial system foreshadows Jesus' work on our behalf. In the Jewish temple, there was a room called the holy of holies. Only the high priest could enter this room, and only once a year (on the Day of Atonement). The room was blocked by a large veil. When Jesus was crucified, the veil was torn (Matthew 27:45–54). Hebrews 10:19-23 alludes to this: "Therefore, brothers, since we have confidence to enter the holy places by the blood of Jesus, by the new and living way that he opened for us through the curtain, that is, through his flesh, and since we have a great priest over the house of God, let us draw near with a true heart in full assurance of faith, with our hearts sprinkled clean from an evil conscience and our bodies washed with pure water. Let us hold fast the confession of our hope without wavering, for he who promised is faithful." Similarly, Hebrews 4:14–16 says, "Since then we have a great high priest who has passed through the heavens, Jesus, the Son of God, let us hold fast our confession. For we do not have a high priest who is unable to sympathize with our weaknesses, but one who in every respect has been tempted as we are, yet without sin. Let us then with confidence draw near to the throne of grace, that we may receive mercy and find grace to help in time of need." It is through Jesus that we have access to God.
Hebrews talks about approaching God boldly in prayer, and we can do so because we know Jesus. The first step of effective prayer is understanding that we can pray only because of Jesus; we approach God based on that merit.
We also recognize that prayer is only effective because it is God who answers it. He has promised to grant requests that are in line with His will (1 John 5:14–15). The more we know God, the more we will understand His heart. We'll know that He is all-powerful and capable of anything (Luke 1:37). We'll know His deep love for people and desire for them to come to Him (2 Peter 3:9). We'll know His jealousy for His glory because it is good, and we will also become jealous for His glory (Exodus 20:5).
We come to know God and His will by His Word—the Bible (2 Timothy 3:16–17). We also come to know God through prayer.
God gives us examples of effective prayer in the Bible. We know that it is not the prayer itself that holds the power, but God Himself. He can stop hungry lions from attacking (Daniel 6), reveal the Lord's armies and save lives (2 Kings 6:15–19), cause earthquakes (Acts 16:25–26), raise people from the dead (John 11; Acts 9:36–43), and more. It is God who is effective, and He invites us to join in His work through prayer.
God also gives us instructions about prayer in His Word. We find that being righteous—that is, following His commands and guidance—underlies effective prayer (James 5:16; 1 Peter 3:12; Psalm 34:15; Proverbs 15:8).
We also see that in our prayers we are to persist (Luke 18:1), pray with faith (James 1:5–8; Mark 11:22–24), be thankful (Philippians 4:6), be forgiving of others (Mark 11:25), pray in Jesus' name (John 14:13–14), and have no sin unconfessed (Isaiah 59:2; 1 John 1:9). Our prayers should be focused on God's glory, not our own selfish gain (James 4:3).
Again, these guidelines aren't about our performance in order to get God to give us what we want. For example, we might persist in a prayer and God can still say "no" to our request. Rather, these guidelines speak to our relationship with God. We cannot expect God to answer our prayers if we refuse to walk in His ways or if we disbelieve Him. If our hearts are not aligned to His, it is unlikely that our prayers will be aligned to His will. When we approach God with grateful hearts that trust in Him and are eager to follow Him, He can change our hearts and mold our character. The accomplishment of His will becomes our deepest desire, and our prayers are offered toward that end.
God tells us to pray continuously and in thanksgiving (1 Thessalonians 5:16–18). We also rely upon the Holy Spirit both to guide us in prayer and to intercede for us (Romans 8:26–27). Prayer is part of the armor of God that helps us to "be strong in the Lord and in the strength of his might" and "be able to stand against the schemes of the devil" (see Ephesians 6:10–18). The more we pray, the more we'll want to pray. We'll come to know God more deeply and see His faithful responses to our prayer. Our hearts will become more like His and our prayers will be more "effective."
So "do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus" (Philippians 4:6–7).
Why pray? What is the purpose of prayer?
How do I know if I'm praying in line with the will of God?
How does a person pray in Jesus' name?
Is there evidence for answered prayer? Does God answer prayer?
What is the importance of daily prayer in the life of a Christian?
Truth about Prayer