In addition to what @hooray suggested, which is absolutely perfect:
- Printed copy of your flights, including return flight.
- Printed hotel confirmation.
- Voltage-switching chargers and cables for your camera and phone.
- Visa if you need one to enter Germany.
- Certificate of health or travel insurance you may have.
- Printed contact information in case of emergency.
Also medicines are preferred in their original packaging. Don't worry too much about hygiene products, they are easily available in Germany although much more expensive than in Colombia (I've been to both last year). For the credit-card, they use Chip-and-PIN cards.