1. Interior Release: Locate the bonnet release lever inside the car. This is usually located near the steering wheel, often under the dashboard on the driver's side, or sometimes near the footwell. It might be a small lever or a knob. It's often marked with a picture of a bonnet or the word "bonnet" (or "hood" in some regions).
2. Exterior Release: Once you've pulled the interior release lever, you'll need to locate the bonnet release catch. This is a small latch located near the front grill, usually under the front edge of the bonnet itself. You'll need to open the bonnet slightly to reach this latch and lift the bonnet fully. You might need to feel around with your fingers to find it, as it's usually not visible.
3. Lifting the Bonnet: After releasing the catch, carefully lift the bonnet. There might be a supporting strut to hold the bonnet open; otherwise, you'll need to prop it up yourself.
If you can't find the interior release lever, consult your owner's manual. A picture will often help locate it. If you're still having trouble, a search online for "2003 Ford Mondeo bonnet release" with images may help.