Christian Apologetics Alliance is how aspiring apologists should use their time and develop their abilities. In a recent thread, members of the CAA addressed this question. Tim McGrew summarized the main points from that discussion, and it is presented here as a featured Apologetics Toolkit post.
(1) Online arguments are not a good training ground for someone who does not have experience. Stay away from them completely until you have studied deeply, and even then, don't just dive into every argument headlong.
This is the hardest piece of advice for most young people to accept, but it is one of the most important. I know how it feels to want to save the world, to stand up to the intellectual bully on Twitter or YouTube or some chat board. But if that is all you do, you will fritter away years in the intellectual shallow end; you'll be at best a playground hero, and sometimes, you'll get your nose bloodied and look like a fool. Take the long view instead. Begin training now for the serious battles, and when they come, in the mercy of God, you will be ready for them.
(2) Get a copy of Greg Koukl's book Tactics and read it very thoughtfully, preferably more than once. It will give you tools for having a conversation when you don't have all of the answers, for those times when the conversation comes to you without your looking for it. Learning how to be gracious in such conversations is a gift beyond price.
(3) Apologetics is only one dimension of Christian life. Serious, lifelong habits of Bible reading and prayer will not appear by themselves; you need to develop them now. Finding a good church is vital. Studying beyond apologetics -- history, literature, poetry, science, art, mathematics, music -- will broaden your understanding and make you a better rounded person, better able to meet others at the point of their own interest. It may also change your view of what counts as apologetics.
(4) For the study of apologetics in particular, ask for good resources and then work on mastering them at a steady pace. There are terrific resources already listed in this thread: videos, podcasts, blog posts, and books. Discover how you best take in information (I prefer reading; a good friend of mine prefers podcasts and audio books) and focus on that method, but do not neglect reading altogether even if you're an auditory kind of person. Find a pace that you can keep up, perhaps half an hour a day, perhaps an hour, and devote that block of time to study.
(5) Find a mentor. If you can find a mentor to whom you can look up as more than just your intellectual superior, someone who can bring you spiritual wisdom and Godly counsel as well as sound scholarship and wide learning, it will change your life almost inconceivably. Perhaps there is no one in your life right now who can play that role. If that is the case, begin now to pray earnestly for God to bring the right person along.
Find out more about the Christian Apologetics Alliance here.