Don't blaze your own way through a natural area. Feet can trample delicate plants and seedlings and can compact the soil, which is harmful to plants. Be aware of which chemicals you are using in your home and garden. Herbicides and pesticides end up in the environment and cause extreme damage. Recycle, recycle, recycle.
Less waste equals less land use for landfills.
Be diligent about using recycled paper products. Compost kitchen scraps. The material is good for the soil and reduces waste. Culprits include Japanese honeysuckle and privet hedge. Support an endangered species, endangered habitat or field-restoration work day.