Trust God by trusting His word. God speaks to us through Holy Scripture. God speaks to us through Jesus Christ our Lord and the Gospel. We trust God by relying upon what He has said through Scripture, Christ, and the Gospel (1 Corinthians 15:1-4).
Trust God even when you don't understand. We cannot understand all the ways of God. Trusting God is confidently believing in His ability to help and direct us. A child is more limited in knowledge than the parents. Yet, that child can trust what the parents say to him. Likewise, our knowledge and understanding of God is limited, but we may confidently trust His word in the Bible.
Trust in the Lord with all your heart, and lean not on your own understanding. In all your ways acknowledge Him, and He shall direct your paths (Proverbs 3:5-6). The word Lord is God's personal and covenant name. Trust God as your Lord by trusting His many wonderful covenant promises in the Bible (e.g., Jeremiah 32:40; Hebrews 13:20-21).
All relationships are built on trust. Our relationship with God is based upon trust, He is trustworthy. His word is our bond of trust. Trust God in all circumstances, then you can say, He is my refuge and my fortress; my God, in Him I will trust (Psalm 91:2).
