Use more coffee grounds
Use a finer grind
Reduce the amount of water
Brew for a longer time
Use a stronger brew ratio
Make sure your coffee maker is clean
Preheat your cup or carafe
Use fresher coffee beans
Avoid over-diluting with milk or water
Try a different brewing method
Check that your filter is not too large or clogged
Stir the grounds before brewing
Use hot enough water
Grind beans just before brewing