I counseled many returning missionaries. I interviewed 1,700 missionaries all over the world. My advice to them is that you should study and prepare for your life's work in a field that you enjoy.
Choose a field that will supply sufficient remuneration to provide adequately for your companion and your children. I bear testimony that these criteria are very important in choosing your life's work.
On occasion we need to make a second effort - and a third effort, and a fourth effort, and as many degrees of effort as may be required to accomplish what we strive to achieve.
Each heartfelt prayer, each Church meeting attended, each worthy friend, each righteous decision, each act of service perfomed all precede that goal of eternal life.