You need a container. A blue 55-gallon plastic drum is the classic choice. They smell like pickles, but they’re cheap. Or buy a fancy terra cotta one for Instagram points.
Important: it must have a screen on top. Mosquitoes are jerks and will turn your rain barrel into a breeding ground. A mesh screen keeps them out and leaves from clogging things.
How to Set Up a Rainwater Collection System & 8 DIY Ideas - OFF-GRID
Raise the barrel up on cinder blocks or a sturdy stand. Gravity is your friend here. It makes filling a watering can way easier than bending over like a sad flamingo.
The Overflow Hole (Don’t Skip This!)
What happens when it rains for a week straight? Your barrel fills up, then what? It doesn’t have a magic “stop” button. Drill a hole near the top of the barrel.
Fit a brass hose fitting into that hole. Attach a garden hose. That hose should point away from your house foundation. You don’t want a moat. You want a happy overflow.
Trust me, discovering a flooded basement is not a fun surprise. It ruins the whole “free water” vibe.