Sending sensor data to InfluxDB from an Arduino Uno can be achieved using the UDP protocol, which requires minimal processing and networking overhead. The InfluxDB line protocol provides a compact way to write data over HTTP or UDP, with points specified as key-value pairs separated by spaces. To enable UDP on InfluxDB, modify the configuration file to specify the database and bind address. A sample code example uses the TMP36 temperature sensor to poll once per second and send the value to the specified InfluxDB host via UDP. Once data is written to InfluxDB, queries can be issued using `curl` or other tools to retrieve it, and troubleshooting tips are provided in case of issues with data collection.