There are several websites that explain ACTS-the following is from Crossroads Fellowship.
The ACTS Prayer Plan - Adoration, Confession, Thanksgiving & Supplication
Prayer is a time to commune with God, to turn to Him to sense His presence, and to know Him more deeply.
Below is a simple guide, The ACTS Plan Of Prayer, to help guide you through the phases of prayer: Adoration, Confession, Thanksgiving, and Supplication.
ADORATION (to praise God)
-- Give honor to God through worship and praise.
"Great is the Lord, and greatly to be praised." Psalm 48:1
CONFESSION (to ask forgiveness)
-- Confess or agree with God for specific issues or instances where you are out of His will.
"If we confess our sins, He is faithful and just to forgive us our sins and to cleanse us from all unrighteousness."
1 John 1:9
THANKSGIVING (to thank God)
-- Lift up praises to God for specific things that He has done.
"In everything give thanks; for this is God's will for you in Christ Jesus." 1 Thessalonians 5:18
SUPPLICATION (to submit a request)
-- Ask God to intercede, guide, and direct your need and the needs of others.
"Be anxious for nothing, but in everything by prayer and supplication with thanksgiving let your requests be made known to God." Philippians 4:6