Are there any ways of not insuring myself?

No. Health insurance is compulsory for employees. However, you are no longer obliged to take out statutory health insurance once your annual income exceeds  69.300 (2024) / vsl. 73.800 (2025) EUR (5.175 (2024) / vsl. 5.512,50 (2025) EUR per month). You can then choose to remain insured on a voluntary basis.