One of the best things any sales rep can do is to keep an objections book. An objections book is a history of your sales calls, including everything you said and did, right or wrong.
After each sales call, you should get into the habit of recording how the meeting went, writing down the key points of the conversation. These notes, if taken consistently over a period of time, will uncover your good and bad sales habits. In order to be successful, you need to be able to point to what works and what doesn't, and an objections book will provide physical references for the future.
Be brutally honest, sometimes a spouse or friend can more easily pick up habits or things that you are saying that are causing a problem.