I don't want to develop german measles. What steps can I take?

Vaccination. German measles is caused by the rubella virus. There are vaccines available to provide you with an immunity to the rubella virus. If you have not had the rubella vaccine, you should see you doctor, or your community health clinic.
MMR vaccine... ...Is safe and highly effective in prevention of rubella, or german measles. Or you can choose to live in a place where everybody but you has had the MMR so you have no one to catch it from.