Being a Christian is more than just believing certain things about God. It is about living in a relationship with God. This relationship is built upon God's love for us and our trust in him. The Bible contains all the information we need to make a decision about what to do.

If you believe that Jesus Christ is the Son of God, that he died on the cross and rose again, and that his death paid the penalty for your sin, then becoming a Christian is very simple.
Either using your own words or the words set out below, you need to say you're sorry to God for living your life without reference to him (that's repentance). Next you need to ask him to forgive you for all your personal sin. You don't have to name each one, but there might be something specific for which you particularly want to ask forgiveness.

Finally, thank God for his forgiveness, thank Jesus for his death on your behalf and welcome him as the new leader of your life.

If you want to do that now then pray this prayer:
Lord Jesus, I'm sorry that I've lived my life so far without you. I'm sorry that I've sinned against you and I ask you to forgive me right now. (I particularly want to confess....). Thank you Lord that you offer me your forgiveness freely, and that you, Jesus, were willing to die on my behalf. I accept your forgiveness now. Lord I invite you to take control of my life, to guide me and be my leader. Come into my life, I welcome you Lord Jesus.

If you've said that prayer for the first time, then I welcome you into God's family

If you're not sure what some of these things mean, for example you don't understand what "sin" means or what it means to "believe that Jesus is the Son of God", then you need more information.
There are lots of books available to help you. You might like to read "Why Jesus?" by Nicky Gumbel, or visit the Christian Enquiry Agency website

Here are some excellent websites you may find useful:

• re:Jesus
• Christian Enquiry Agency