Your prep work and the quality of paint you buy will determine how long the paint lasts. You might spend a small more time and money, but the results will last for years before you have to re-coat.

Clean the bricks well to remove soot, dust, etc. Use a excellent scrub brush with a TSP solution or a cleaner made specifically for brick.

It is extremely vital to buy a paint made for masonry. Since brick is very porous and can have a powdery surface, it needs to be paint that will both seal and adhere. It sounds obvious, but read the mark and talk to the person at the paint desk for instructions specific to that product.

Excellent luck!

First you need to clean the brick like others have mentioned. Then a tip I heard on HGTV was to spray the brick down with water just before you start to paint. Brick is very porous and this will help you greatly. Spray a section at a time as you go along . Use a large napped roller not the fine ones that you would use painting a wall. Then touch up with a paint brush anything you may have missed.

buy some paint and a roller and away you go

It’s really vital to clean the bricks excellent before painting them or they’ll peel in a small time. Using a stiff brush and some TSP in water scrub the bricks, rinse and let them dry at least 24 hours. Then paint with a primer first, using a long nap roller. After it is dry you can paint using a excellent quality paint and a long nap roller again.
Excellent luck with your project!

When I painted mine, I used a roller with a heavy nap. Then I had to go over it with a brush to get the places the roller didn’t cover. Those were the areas in the bricks that were unusually deep.