Later in Scripture we see that the twelve were called for the purpose of being prepared and sent out to make other disciples. After having been prepared, others could clearly see that they have been with Jesus and they were blameless in their dealings while they were on the mission field. Each step of the process was very intentional achieving the results intended by Christ in selection of his disciples, teaching them to be like Him, sending them out to reproduce what they had been taught while being a blameless witness for Jesus.
This methodical approach is the intended method by which discipleship is to be carried out by the church. The first step is coming to Christ. After this, spending time with Him and learning how to become more like him is essential. Once this preparation is complete, then we are to go out into the world and reproduce this process making other disciples always mindful that we are being watched by those around us looking for a way to discredit this work.