The most practical way to do this is to ensure that your indoor air CO2 levels aren't significantly elevated over outdoor levels. One common way to do that (apart from opening windows) is to use a balanced ventilation system like an ERV or HRV. Those constantly exchange indoor air for outdoor air, and exchange a lot of the heat in the process to reduce energy losses.
Doesn't help if atmospheric CO2 levels increase to unsafe levels, though.
Doesn't help if atmospheric CO2 levels increase to unsafe levels, though.