Things like vats of liquified cow feces stored underground, which are later sprayed on (organic!) crops - these have a much larger impact than a few cows producing their feces, which is later composted. Cows produce methane, as do chickens.

The thing is - how is the average person going to improve the processes? People can eat less meat and urge the governments in different areas to force better farming practices through regulation, financial support for upgrades, investment in technology (for example, something that composts manure and spreads it better than the liquid manure we keep in vats or somehow breeding cows that produce less methane), and other such things.

Some countries will be able to pull this off. Others... well, will fail. And some of those are either major contributors or consumers.