To be honest, I think the role of a disciple is quite simple (please notice I did not say easy). God in His Word has given to us the means of grace by which the Christian is to grow in his faith. According to Acts 2:42-47,
And they devoted themselves to the apostles' teaching and the fellowship, to the breaking of bread and the prayers. And awe came upon every soul, and many wonders and signs were being done through the apostles. And all who believed were together and had all things in common. And they were selling their possessions and belongings and distributing the proceeds to all, as any had need. And day by day, attending the temple together and breaking bread in their homes, they received their food with glad and generous hearts, praising God and having favor with all the people. And the Lord added to their number day by day those who were being saved.
First, if you follow the reading of the text, the crowd had just listened to Peter's sermon. When they asked what should they do to be saved, Peter commands them to repent and be baptized. As followers of Christ, it is that simple. Repent and be baptized into the community of believers in Christ. Then "they" devoted themselves to the Apostle's teaching. In other words, they became listeners. They sat at the feet of those entrusted with the Gospel and submitted to God's Word. So the Gospel was announced in preaching and in the baptism and the new converts believed and identified themselves with Christ by repenting and being baptized.
The text goes on to mention that they broke bread. So as a community of baptized believers, and as other parts of the New Testament inform us, they took part of the Lord's Table. They fellow-shipped with each other using the means of grace God had provided including prayer and praise. There were no programs. No books on marriage. No 12 step self help program. The Apostles simply preached a message where they explained the law of God and then demonstrated how the law pointed us to Christ.
For example, we know in the NT that marriage is good and divorce is wrong based in the law in the created order, but the Apostles didn't stop there. They demonstrated what marriage was for in the first place. They used the Gospel and not the law to motivate the people of God to die to themselves. It was in praise of Christ and what He had accomplished that caused Christians to obey.
Which leads to the last point of the text. The Christians in Acts 2 did good works in meeting each others needs because they had sat at the table and heard from God in the presentation of Christ. They ate and had their spiritual fill. Because their needs were met through the means of grace that God had provided in preaching, baptism, Lord's Supper, prayer and praise, they then turned to make certain those who were in need had their needs met.
My point is that being a disciple is not a call to go change the world. It is a call to come out of the world while still living in it. It is a call to submit to Christ's Lordship. It is a call to recognize our true source of life in the words of Christ's Gospel. It is to gather together with the Saints and use the means of grace God has given to His people. It is to listen to what God has said and allow Him to change us with a message that is outside of us...a message of Christ and His finished work. By so doing, Christians will become the very Salt and Light that programs can never accomplish.