Pan frying fish, The French call it 'saut?,? it's a great way of cooking most types of fish fillets as well as some whole fish. Pat the fish dry with clean kitchen paper and make 3 or 4 shallow slashes across the skin side of the fish and portion the fillets if necessary.
Heat a non-stick frying pan or skillet until hot, add a little olive or sunflower oil. Lay the fish into the pan away from you skin side down so that any oil that might splash from the pan doesn't burn you.
Allow the fish to start to crisp up, turn the heat down and allow it to cook until almost finished cooking; then leave the fish in the pan for a couple of minutes to finish cooking. If you are cooking fillets, turn them over on to the flesh side and immediately turn the heat off. There will be sufficient residual heat in the pan to finish the cooking process.
If you are cooking a whole fish, place the pan into a hot oven (200C / 380-400F) and leave until cooked; this will depend on the thickness of the fish. Squeeze Lemon juice over the fish and season to taste with sea salt and black pepper, add extra virgin olive oil to taste.
As the fillets of fish start to cook, the cut sides will change colour from raw opaque to creamy white cooked. The more that the colour changes the closer to being cooked they are, when light pressure on a fillet starts to separate its flakes, it is cooked.

[I posted this recipe.]