The three main principles of trash reduction are Reduce, Reuse, Recycle.
To reduce, buy things with less packaging, and always shop with reusable bags, use steel water bottle instead of plastic ones, or filter your water at home.
Reusing can be as simple as using the backs of printed pages for scrap paper and lists, etc.
Recycling is as simple as putting recyclable items in the right place, which is NOT the trash.

If we all try to do all three as much as possible, and ask our family and friends to do the same, we can really have an IMPACT!