Making a decision for Christ involves:
1)  Admitting that you have sinned.  2.) Believing in Jesus.  3.) Confessing that Jesus is Lord.      
Romans 3:23
"For all have sinned and fall short of the glory of God"
Romans 6:23
"For the wages of sin is death, but the gift of God is eternal life in Christ Jesus our Lord. "
John 3:16
"For God so loved the world that he gave his one and only Son, that whoever believes in him shall not perish but have eternal life."
1 John 1:9
 "If we confess our sins, he is faithful and just and will forgive us our sins and purify us from all unrighteousness. "