Pick three shades: If you find a color you enjoy, test lighter or darker shades, as well, to see which one you like the best on your walls. Slight shades can make a big difference.
Paint the samples on the wall or boards: You can swatch the paint samples directly on the wall or on a poster board. Both can be good options as long as you cover a big enough space to see exactly what the color looks like in the room.
Swatch on multiple walls: Paint colors may look different on multiple walls in the room. To ensure you choose the right shade, swatch on various walls to see how it looks in certain lighting or next to pieces of furniture.
Consider a primer: If the paint color you're testing is on an existing deep or bright shade, it might help to use a primer before swatching.