King James Version
For God so loved the world that he gave his only begotten Son, that whosoever believeth in him should not perish, but have everlasting life.
New International Version (NIV)
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.
Romans 10:9-11 tells us:
That if you confess with your mouth, "Jesus is Lord," and believe in your heart that God raised him from the dead, you will be saved.
For it is with your heart that you believe and are justified, and it is with your mouth that you confess and are saved. - (NIV)
Here is a link to Teen Missions page for the Steps to Salvation. They call it the ABCS of Salvation. I love how clearly they have illustrated it.
The ABCs of Salvation - Teen Missions International.
Blessings in Christ.