Line a fine-mesh strainer with cheesecloth, a coffee filter, or a clean kitchen towel
Place the lined strainer over a bowl
Spoon the yogurt into the lined strainer
Cover the yogurt loosely
Refrigerate while it drains
Let it strain for 1 to 24 hours, depending on desired thickness
Check the yogurt occasionally and discard or save the drained liquid if desired
Transfer the strained yogurt to a clean container
Stir before serving if needed