Scaling whole fish is a necessary chore as the scales are unpleasant to eat. Your fishmonger will be happy to gut and scale fish for you but it is also an easy and satisfying technique to master at home.
Removing scales can be a messy business so put the fish into a plastic bag to catch the scales.
Use a fish scaler or the back of a knife
Hold the fish firmly by the tail and scrape the knife from the tail to the head of the fish removing the scales in a stroking motion – they should flake off quite easily