"Believe in the Lord Jesus Christ, and you will be saved." - Acts 16:31

There are time when the Bible is, admittedly, hard to understand.  There are passages of Scripture that baffle Bible scholars and provoke endless debate.  However, when God wishes to make something plain to us, he doesn't waste time with making the message any more than it has to be.  When Paul and Silas were asked by the jailer in Philippi (just after an earthquake had caused the building to collapse, but all of the prisoners had remained in their cells because of Paul's preaching), "Sirs, what must I do to be saved?" the answer was remarkably simple.  Paul simply replied, "Believe in the Lord Jesus Christ, and you will be saved."
It is amazing to me how we can overcomplicated such a simple message.  How the Church can take God's one sentence offer of salvation for those who believe in his Son and turn it into a massive tome.  The message itself is complete without any embelishments.  There isn't anything else we can do to be saved, there isn't anything else we have to do to be saved.  There isn't anyone or anything else that we can put our faith in that will get us the result of salvation promised by Jesus.
And yet, over the centuries, we've allowed other things to creep in, we've made the test of faith harder for those on the outside to pass.  We've forgotten that we too were saved by the blood of the Lamb and that without Jesus we'd be as lost and fallen as anyone.  I had a basketball coach that liked to recite an acronymn that he was sure teenage boys would remember: Keep It Simple Stupid.  He didn't want us to overcomplicate the sport, but the sentiment applies here as well.  The message was simple and straightforward when Jesus spoke it, it was simple and straightforward when Luke wrote Acts, and it should be simple and straightforward when we tell it to the world today.
What about good deeds, don't I have to prove that I'm worthy?  That comes later.  Once we become Christians we prove that our faith is genuine by obeying God's laws and following the teachings of Jesus, but those deeds alone will never save us.  They're part of a process of becoming like Christ that will occupy the rest of our lives as we seek to removed impurities through the grace of God.  Rest assured, if someone tells you that you need to be good before you can be a Christian they don't know what they're talking about.
The message is simple, "Believe in the Lord Jesus, and you will be saved."