A 5-gallon bucket of paint is tricky to pour from without causing a mess, especially when it is full. Install a specialty spout on the lid to gain better control over the paint and to greatly cut down on spills. Add the spout and pour the paint once the paint is already mixed, either by a store representative or at home with a drill-operated paint stirrer.
Set the plastic tarp on level ground in your work area. Set the paint container on top of the tarp.
Remove the screw cap on the top of the paint lid by turning it counter-clockwise. The screw cap covers a smaller hole, much like a larger version of the cap and spout on an orange juice carton. If the lid has no capped hole, purchase a replacement lid that does.
Attach the spout to the threaded hole on the pail lid by turning it clockwise atop the threads. Tighten the spout so that it slopes toward the nearest part of the rim's lid.
Tilt the paint pail slightly toward the empty paint container or tray, lining it up so the spout points downward. Twist the spout if necessary to adjust its alignment. Tilt only a little at a time, allowing gravity to pull the paint down the spout.
Tip the paint bucket back upright once you've poured the desired amount of paint into the container or tray.