By Regulation:
In 1992 at Rio, Brazil, people gathered together from all over the world to discuss about global climate change and its damage. They defined the cause is increase in atmospheric CO2 due to overuse of energy in industry, home, and commercials, so to minimize the effect, they made an agreement of UNFCCC(United Nations Framework Convention on Climate Change). So far, more than 184 countries joined this and South Korea joined in 1993, Dec. In 1995 January, people agreed on that this UNFCCC is not enough to actually prevent the global climate change, and agreed on Kyoto Protocol to force developed countries to minimize CO2 emission. The countries on Appendix I promised to reduce 5.2% of the emission until 2012 from 2008. Also they introduced the concept of CO2 emission trade system, so that they can help each other in technological ways. These two agreements are very well-known ones, and other than this, there are many huge and small campaigns locally, nationally and internationally to minimize CO2 emission.
What we can do:
There are few ways to prevent the ocean acidification. Obviously, since the cause is increasing atmospheric CO2, we obviously need to reduce CO2 emissions. We are already quite familiar with ways to reduce CO2 emissions. Also worlds put a lot of efforts to reduce CO2 emissions, such as CO2 emission trade, Paris Agreement, Kyoto Protocol and so on. Personally in homes, we can purchase products with high energy efficiency, save resources, recycle what we can, and frequently use public transportation rather than our own mobiles.
Do be more technical, we also have another way to solve this issue, called Climate engineering (such as iron fertilizations). The diagram below is provided by Geoengineering Monitor and list possible climate engineering technologies to prevent climate change. There are climate-ready crops, white painting, space mirrors, cloud seeding, engineered microbes, enhanced weathering, ocean fertilizations, and biochair. The details of each technology is explained below the terms.