Use more than one measurement
Follow the manufacturer’s instructions for chest and any additional measurements. Check that the harness stays secure without rubbing or interfering with normal movement. Recheck fit after adjusting every strap rather than assuming one setting fixes the whole harness.
Try it in a quiet place
Let the dog investigate the equipment and introduce wearing it gradually. Test the setup inside a secure area with an adult handler. Watch what happens when the dog turns or steps backward; do not discover an escape risk beside traffic.
Review it as part of the routine
Inspect clips and webbing before walks. Growth, weight changes and seasonal coat changes may alter fit. If you are struggling to control the dog, ask a qualified trainer for help with the complete walking plan rather than relying on a different attachment point alone.