If you plan on using your planter outdoors, removing the drainage plugs is a great way to ensure that water in the soil can drain freely and your plants stay healthy!
To remove the drainage plug, insert your hand inside the planter and twist the plug counterclockwise. After a few turns, it will loosen up and fall out from underneath the planter.
For taller planters, it may be helpful to place the planter sideways on top of a surface such as a table.