Download audio lessons for German onto an mp3 player. The audio lessons should match the German coursework you are currently studying. Set the volume for the lowest possible volume that you are able to hear. Higher volume will interfere with your sleep. Put your headphones on and play the recording as you go to sleep. The mp3 player should continue to play the lessons as you sleep, allowing them to be absorbed by your subconscious.
Install subliminal message software for German onto your computer. The software should flash German words on the screen as you work on your computer during the day. The messages will be too fast for your conscious mind to notice, only being picked up by your subconscious. This will help to reinforce and familiarize you with German.
Practice reading, writing, speaking and listening to German for at least 30 minutes every day using your German course pack. A German course pack should include a textbook divided into different lessons and also include an audio CD that you can listen to to practice your pronunciation and listening. Subliminal learning will not help you learn German unless you are also actively learning the language every day. Subliminal messages will help you remember and acquire German more quickly.