Go, therefore, and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe everything I have commanded you. And remember, I am with you always, to the end of the age.
I love the phrase "teaching them to observe everything I have commanded you." In this one statement, Jesus issues a self-replicating command to the disciples to tell others to do everything Jesus commanded, including the telling of others to do the same. Paul issues a similar command to Timothy:
And what you have heard from me in the presence of many witnesses, commit to faithful men who will be able to teach others also. 2 Timothy 2:2
In 2 Timothy 2:24, Paul states that followers of Jesus must be "able to teach", and Peter tells his readers to always be ready to "give a defense" for what they believe (1 Peter 3:15), that is, to teach those who question the faith why it is true. In Colossians 3:16, Paul encourages believers there to teach and admonish one another in all wisdom, and the writer of Hebrews laments the fact that his readers are still struggling over basic doctrines and not already teachers themselves (Hebrews 5:12). Teaching others about Jesus and how to be like Him is at the very heart of what it means to be a disciple of Jesus.
Probably the biggest obstacle for most people in embracing this idea to be teachers is thinking that they don't know enough to teach others. If this describes you, I would encourage you to spend some time looking at 1 Corinthians 2, especially verses 10-14. The essence of these verses is that no one understands the thoughts and ideas of God unless the Spirit reveals that understanding, and no one is able to speak in such a way to bring understanding about spiritual things except by the Spirit. As a follower of Jesus Christ, you meet the only qualification necessary to explain to someone else what God has revealed to you: being indwelt by the Holy Spirit.
This doesn't mean, however, that one can speak "by the Spirit" apart from or contrary to God's Word. God says He will be found by those who seek Him will all their hearts (Jeremiah 29:13) and that the spirit of the "prophets", that is those who claim to speak on God's behalf, must be in line with or subject to the Prophets, in context meaning the Word of God (1 Corinthians 14:32). You cannot teach what you do not know, so spending time in the Word and living out what you learn is an important prequisite to teaching your understanding to others. But from the moment you read and understand anything of the Bible, by God's Spirit you are qualified to teach that new understanding to someone else.
As you seek God in both Word and deed, under the guidance of an older brother or sister, don't be afraid to be an older brother or sister to those not as far down the path of life and faith as you are. Paul not only learned from Barnabas, he taught Titus and Timothy and countless others. Timothy not only learned from Paul, he taught many others as well. The life of a disciple is never meant to be lived in isolation, and your younger brothers and sisters need you to teach them about your faith journey, both to follow in your steps to joy and avoid the paths you took that lead to hardships.
Disciples will teach, both as an act of loving obedience to the Father and as an act love to their siblings in the faith.
Praise the God and Father of our Lord Jesus Christ, the Father of mercies and the God of all comfort. He comforts us in all our affliction, so that we may be able to comfort those who are in any kind of affliction, through the comfort we ourselves receive from God. For as the sufferings of Christ overflow to us, so through Christ our comfort also overflows.
2 Corinthians 1:3-5