Phil. 4:6 Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving, let your requests be made known to God;
Phil. 4:7 and the peace of God, which surpasses all understanding, will guard your hearts and minds through Christ Jesus.
We are not to be anxious (worry) about anything yet many Christians do. Worrying robs your faith. You cannot be in faith and worry at the same time. So how can we live a care free life? We take every care that would try to take hold of us and we cast that care over onto God because He cares for you (1 Peter 5:7). You do this in prayer until you have released it to God. Then keep your focus on what God has said in His Word. Continue to confess the Word over your circumstances.
When the temptation comes to take that care back, resist that temptation by giving God thanks for what He has promised in the Word of God. Maintain a confession of thanksgiving instead of talking about and magnifying the problem. In maintaining a confession of thanks to God for His promises, the peace of God will guard your heart and mind from worry. So refuse to think about and meditate on what leads you to worry by confessing and meditating on God’s Word. You can master what you choose to think about and when you do you can be free from worry.