Striking is the term used to describe the action of setting the hook in the fish when you get a bite.
It is not usually necessary to do more than move the rod swiftly back a few inches with a flick, but when fishing at range, or if there is a lot of slack line between you and your tackle, you may need to strike with a sweeping action to pick up the slack line and make contact with the fish.
Speed of the strike is much more important than power as all you are trying to do is pull the hook firmly into the mouth of the fish before it has time to eject the bait.
As a general rule, keep in mind that the closer in you are fishing, the less powerfully you need to strike.
An unnecessarily powerful strike when fishing at close range will result in your tackle being pulled out of the water, sometimes with a small fish attached! There is no surer way that I know of to get your tackle in a tangle!
Playing Fish
Small fish can be wound in quite easily and then swung to hand, but large fish are capable of long sustained fights during which you may have to give line.
When you hook a large fish, do not try to bully it out of the water as quickly as possible, your aim is to tire the fish so that when all of the fight has gone out of it, you can draw it safely over the landing net.
Large fish will try to swim away from you as fast as they can when they are hooked, or soon after as they feel resistance. You will usually need to give line to prevent a break or the hook pulling free and this can be done in two ways.
Most reels are equipped with a slipping clutch. This allows the spool to rotate to give line when the pull is approaching that which would break the line. An alternative is to allow the fish to take line under pressure by winding the reel backwards. Personally I prefer to backwind, using judgement to determine when giving line is necessary. If you do choose to use the slipping clutch, make sure it is set to just below the breaking strain of the line. Too slack and you will struggle to recover line, too tight and you risk a break.
Playing a fish is a little like a tug of war match. You give a little, you gain a little until eventually the fish is tired. To gain the maximum advantage from your tackle it is essential that you use the rod to cushion the lunges of the fish, so most of the time you should hold it high. This applies maximum pressure on the fish, and also prevents it from coming too high in the water before it is ready for the net.
The exception to this is when you need to stop a fish from reaching an obstruction such as a weed bed or some tree roots. If you lock down the reel and try to stop the fish by holding the rod high you may pull out the hook or break the line. When you need to stop a fish in this way, drop the rod tip so you are applying ‘side strain’. Usually this will force the fish up nearer the surface and is often enough to make it change direction away from the snag.
Learning to play a fish well is something that only experience can teach you, but with perseverance you will develop an instinct for when a fish is ready to be brought to the net.