Research 

Make sure to research the company and who is going to be interviewing you so you can be well prepared. Blow them away with your knowledge.

Practice 

Practice makes perfect every time. So keep trying until you feel confident. Even practice in front of a mirror I know it sounds silly, but every bit helps.

Make It Personal 

Give them a reason to remember you, a small part, a unique story about you so they can look back and have something to remember you by aside from what is on a piece of paper. People want to work with people they feel like they can get coffee with, so make them feel like they can get coffee with you.

Ask Questions 

It shows that you are interested in the job, whether they are weird questions or ones about the job, make sure to ask some.

Take Your Weakness and Turn Them Into Strengths 

Not every weakness is a weakness, show them how you took one of your weakness or mistakes and grew from it or used learned from it or turned it into a strength.

Think Positive 

Thinking negatively will get you down and then you won't feel confident and you should feel confident because you are amazing.

Close On A Positive Note

Shake hands, smile, make sure you end it on a positive, ending on a negative note is never a good thing.

Bring A Copy Of Your Resume 

Make sure to be prepared and bring what you think you need to just in case, it never hurts to be prepared. This means samples of previous work you have done as well.

Be Prepared 

Always, always, always be prepared. Practice and get all the information a head of time.

Plan Your Outfit Ahead Of Time

Make sure you are dressing appropriately for the type of interview you are going to and for the job you want. Dress for the job you want.

Write Thank You Notes

These leaves such a good impression and something to show your gratitude and leaves a mark. Handwritten are more meaningful, but these days everyone has their faces in their computers so send them an email!

Make Sure To Network 

Even if you do not get the job you still have an amazing opportunity to network and you now know someone in the field you are interested in.

Be On Time

It never leaves a good impression being late. Make sure you are on time, even better be a few minutes early.

Follow Up (If Required)

If you haven't heard back in a reasonable amount of time follow up, it also shows you are interested.

Be Polite 

Being polite can go such a long way, being respectful can make such a good impression.

Be Confident 

If you don't feel confident in yourself and your abilities they will know. Being prepared and practicing can help you feel confident and confidence is always a good thing to have.