Thank the interviewer(s) in person, by email or by post. Common courtesy, alongside politeness really helps in interviews.
Never be late. Prepare for the unexpected.
Don't brag too much. Being humble is powerful.
Keep your words work-safe during the interview.
Don't be scared to say you don't know the response to questions. Don't lie.
Eat a healthy breakfast before - don't have stinky ingredients!
Job Hunting Tips:
"Produce jobseeking materials and develop jobseeking skill. After your selected career choices are chosen, your CV and cover letters can be tweaked to reflect your talents as they relate to the of possible companies."
Some useful things would be:
Proven sales and/or telesales experience
Be able to provide references from other roles
A background in a comparable position with at least 1 year experience
Should possess proven experience in sales negotiation