First, set up the FreeStyle Libre app or compatible reader. Select a suitable area on the back of your upper arm, wash and dry the skin, then clean it with an alcohol wipe and allow it to air‑dry. Apply the sensor with the provided applicator and activate it using the app or reader as instructed. The sensor usually requires about a 60‑minute warm‑up period before glucose readings become available. Always follow the instructions supplied with your specific FreeStyle Libre model, as setup steps may vary slightly between versions.