The most important advice I can give you is to seek God's will. He knows all about you; after all, He made you. And He not only knows all about you, but He also loves you and knows what's best for you. Make it your goal to seek His will for your life.
What is His will? I don't know exactly what He wants you to do after you graduate, of course -- but I do know this: The first step is for you to turn your life over to Him by asking Jesus Christ to come into your heart and mind. Confess your sins to Him -- not only what you've done that you shouldn't have done, but also what you've failed to do. Then thank Him that you are now His child forever -- beginning today.
Then ask God to guide you. How does He do this? One way He guides us is by His Word, the Bible. Through it we learn what's important in life, and we also learn how we ought to live. In addition, God has given us the privilege of prayer. Pray every day about your future, and ask God to guide you by His Spirit.
God also often guides us through the circumstances of our lives. Ask Him to show you what abilities He's given you, and ask Him also to direct you to a place where they can be used. God's promise is for you: "In all your ways acknowledge him, and he will make your paths straight" (Proverbs 3:6).