By confessing your sins to God and placing your faith/trust in the finished work (death, burial, and resurrection) of Jesus Christ our Savior.
Rom. 10:17 So then faith comes by hearing, and hearing by the word of God.
Heb. 11:1 Now faith is the substance of things hoped for, the evidence of things not seen.
Heb. 11:6 But without faith it is impossible to please Him, for he who comes to God must believe that He is, and that He is a rewarder of those who diligently seek Him.