The most common mistake is to hold off making a decision about your vocation until you have paid off all your bills. Although dioceses and religious orders vary in their policies, you need to make a firm commitment in favor of your vocation. Be resolute and passionate about hearing God's voice in our noisy world. You will discover that as soon as you make the decision to clarify God's calling, your needs will change along with your spending and saving habits.
The key is to say "yes!" to God and to yourself. Wish no more than this: to do God's will. Then, make it so in your life.