If you know your pool needs a shock dose of chlorine, there are some simple steps that you can take in order to accomplish that task. The first task is to buy the shock, either liquid of powdered from your local swimming supply store. If you have a non chlorinated pool use non chlorinated shock and the same thing if you have a chlorinated pool. If you are not sure which kind to buy ask the salesman what you need for your style pool and style filter.
Then read the directions and put in the right amount of shock. The manufacturer should have a chart to advise you how much chlorine you will need. You will have to have a fair idea of how big your swimming pool is. If you feel like you have put in too much, that's ok because you cannot over shock a pool with chlorine. The amount of chlorine that you will need, will vary on the size of your pool plus how green it is. If you purchased the liquid shock, simply pour it into the pool itself from the deep end.
Always add shock to water not water to shock. Wear clothes you don't care about cause they might get bleached. Warm water dissolves shock faster than cold, its your choice. Use a wooden stick and stir around the shock making sure it gets all dissolved or as much as your can. Pour the bucket of shock all around your pool or heave some in the middle. You may have some undissolved shock at the bottom of your bucket. In this case just dip your bucket in some pool water give it a swish around and pour it back into the pool to help dissolve some of that shock.
Most shocks require at least 8 hours with no one in the pool read the label before adding shock. Also some dealers will tell you to add shock directly to your skimmer. This is not a good idea especially if you have chlorine or an automatic chlorinator. Reason being is because calcium hypo and tri-chlor, which can be found in chlorine tablets, creates a harmful chlorine gas. To get to the point, your automatic chlorinator could explode. It's happened.
Chlorine-free shock is also superior to chlorine based pool shock for normal weekly shocking because of the inert ingredients and fillers that are used in the product. Each time chlorine based (Calcium-Hypochlorite) swimming pool Shock is added to your water, you are adding calcium to the pool. This may eventually raise the calcium hardness level of the water, causing cloudiness or scaling along the water line.