Here are general instructions for using a metered dose inhaler and spacer.
To begin, shake the inhaler five or six times.
Remove the mouthpiece cover and place the spacer over the mouthpiece at the end of the inhaler. Put your lips and teeth over the spacer and breathe in slowly. As you do so, squeeze the top of the canister once. Keep inhaling even after you finish the squeeze.
Continue inhaling slowly and deeply. After inhaling, remove the spacer from your mouth and hold your breath for up to 10 seconds. If you need another dose of medication, repeat the previous steps.
Your inhaler may come with slightly different instructions. Ask your doctor for a demonstration.