Serving your church and your faith is a tall order to ask of most people, and there's no cookie cutter format on how to become a missionary. However, there are some basic guidelines that may help shape your decision to dedicate your life to your faith.
There are several ways in which you can become a missionary. You may serve in your church and go on a mission when one is scheduled, such as a short term visit to a developing country. Missionary services may be needed to distribute medical or food supplies; these may run on a temporary basis. This type of missionary service is usually voluntary and without compensation. On the other hand, your church or organization may ask for a long-term commitment and offer a modest salary for a more detailed job requiring full-time employment. Either way, becoming a missionary is a calling and a step you should not take unless you are prepared to make a serious commitment.
For individuals interested in a short-term length of service, inquire with your local church about any overseas projects they are funding; ask if you may be of help for a few weeks. Perhaps you have some special skills that you could contribute such as professional expertise - or you may speak a foreign language and could teach others.
If your goal is to become a staff member on missionary events, then get all the education you can before you enlist your services. Money may be tight for years to come, and a quality education earned beforehand will serve you well as it will better prepare you for placement within the organization. There are many mission fields operated by international food banks and disaster relief programs; any of these would be thrilled to have a dedicated full-time staff member. So don't rush your life to get there early, as you will be better equipped to serve if you plan wisely and take your time.
Another critical decision to make is whether to marry or remain single. You will certainly have your freedom to devote your time and energy to mission work if you are single, but this life choice may be too difficult for some. However, if you meet and marry someone in your field that shares your vision in life, being married may prove to make your missionary service even stronger. Persons that are already married before becoming missionaries may find strong opposition coming from the partner who is left behind. Becoming a missionary will be a tough decision at any stage in life, so remain open to all possibilities and go where your heart leads.