C. Michael Patton from Reclaiming the Mind and Credo House has written a great little book to help new believers become disciples – Now That I'm a Christian: What It Means to Follow Jesus. I say "little" book not to demean it or even because it's that much briefer than other books, but because it's not intimidating. It's just the right length to cover a variety of important topics to get a new believer started without overwhelming him.
Patton covers basic Christian beliefs and fundamental Christian practices, the kinds of things every Christian should believe and do to be faithful to God's teaching in the Bible and get grounded in the faith to build a firm foundation for lifelong growth. He covers five basic Christian beliefs: Bible, Man, God, Christ, Faith. These will start a new Christian developing a firm understanding and a coherent worldview that makes sense of Christianity and living in the world as a new believer. He then goes on to cover some basic activities Christians should engage in regularly: prayer, study, church, mission. And he includes a chapter on suffering so that new believers have an accurate understanding to hold onto when hard times hit.
Patton writes in an accessible way and introduces new terms and vocabulary without dumbing it down.
It can be given to someone curious about what Christianity is all about, how it makes sense. It's accessible for students to give them a more coherent understanding of their faith.
I haven't seen a good book – a handbook really – to disciple new believers, and even long time Christians, in quite some time. And I really like this one. It fills a very important purpose to make disciples, not just converts.