While it is better to let a professional handle this, the first step is to cut off the irrigation system's water supply. Your irrigation system's main shut-off valve must be protected from freezing. To protect it from harsh winter temperatures and to keep it from freezing, wrap it in insulation (foam insulation tape and a plastic bag). If you do not have a main shut-off valve, you should consider installing one as a precautionary measure. Any above-ground piping must also be insulated. Self-sticking foam insulating tape or foam insulating tubes, which are widely available at home improvement stores, are suitable.
You must now remove the water from the sprinklers and pipes so that it does not freeze and burst the pipe. You can drain your pipes using a manual drain valve, an automatic drain valve, or the compressed air blow-out method. However, because there may be safety concerns, we recommend contacting your local irrigation specialist. Many companies provide sprinkler winterization services.