1. You are smart and you know what you are talking about.
Be confident in that and respect yourself because you do know a lot. If you don't know something ask for help and be direct and open that you don't know.
2. You are trying to help them.
Remind yourself what your job is. If you are in sales for the right reason you are doing this because you want to help someone solve some type of problem. Keep that focus on helping people and your confidence will rise as your prospects feel that you genuinely care about them and want to help them.
3. Look at your deals you have closed.
Take a look at your successes. Remember them and think about why those deals closed. Take a step back and think about why those things worked out. This will help guide you and give you more confidence with your current deals.
4. Fake it.
Prospects can tell when you are not feeling good about yourself. You can tell it in your voice, in your process, things start to go badly and that is because your confidence is down. Recognize this feeling and be aware of it. Try to fake it and it will eventually turn around. Things can only go up right?
5. Break out of habits.
Sales can be monotonous. You should try new things. Break out of the old habits and try to embrace new ones.
6. Work harder than ever.
There is one pretty stable thing about sales. If you prospect more, if you work harder and more you will get more done. There is really no way around it. Try really, really hard when your confidence is down because things will come out of that hard work.
7. Focus on a goal.
Why are you doing what you are doing? Think about your personal and professional goals and that should give you a boost of energy and confidence.
8. Ask for help.
Everyone needs help sometimes. You are not alone. There are other people on your team that have rough spots too. You don't need to feel ashamed. Ask your manager or your peers for some help and guidance. Usually people do want to help. :)
9. Take a day off.
Regroup and get yourself in the right spot. Complain to someone, get all your bad energy out, scream, cry, etc. Get all the emotions out and come in after that day off and get down to some serious work. You should feel refreshed and ready to go.
10. Call a customer of yours.
Talk to a customer of yours that is happy. Understand what they liked and didn't like about the sales process. This should help your confidence to rise hearing about a happy customer that you closed. Understand what they are saying and remind yourself that you are meant to be doing this.