Question: must lose 20 lbs fast?
Answer: Count Calories. It may sound like a no-brainer, but counting calories is one of the easiest and most effective ways to start losing weight fast. ... 
Drink More Water. ... 
Increase Your Protein Intake. ... 
Cut Your Carb Consumption. ... 
Start Lifting Weights. ... 
Eat More Fiber. ... 
Set a Sleep Schedule. ... 
Stay Accountable.