Clean the lint screen after every load and watch for drying cycles that suddenly take longer. A hot laundry room, damp clothing after a full cycle, a burning odour or a weak exterior exhaust all deserve attention.
Use the right connector
Crushed foil and unsuitable plastic connectors trap lint and reduce airflow. Follow the dryer manufacturer and local code requirements for the appliance connection and exhaust route.
Clean the full route
A household kit may not reach a long run, roof termination or several elbows. Professional dryer vent cleaning addresses the route from appliance to exterior and checks the termination flap.