How to troubleshoot engine misfire in a Ford Focus?

I have been experiencing engine misfiring in my Ford Focus. It usually happens when I am driving at high speeds. What could be the cause of this issue and how can I fix it?

It could be a problem with your spark plugs or ignition coils. Have them checked and replaced if necessary.

Check the fuel injectors for any clogs or leaks. Those can also cause misfiring in the engine.

Make sure your air filter is clean and not clogged. A dirty air filter can affect the engine's performance.