Dig around the web, read some books, watch some videos, do some research. Look for people that are paving the way like Ben Falk, Richard Perkins, Geoff Lawton, Bill Mollison, Masanobu Fukuoka, John Liu, Jadav Payeng (Forest Man). Look for subject matter under permaculture, edible food forests, no-work gardening, clay seed balls, seed bombs, guerrilla gardening. There are lot of great ideas out there.
Getting into the mechanics of the way we garden and farm, a major shift is going to be an environmental necessity. We have been in the habit of extracting without replenishing.
Every project, no matter how small or how large, starts with one person making the decision to change.