Interact subtly on the company's social accounts - perhaps make a comment.
Take time with your answers. Don't feel pressure to answer quick fire.
Thank the interviewer(s) in person, by email or by post. Common courtesy and politeness really helps in interviewing.
Don't be scared to admit you don't know the answer to a question. Don't lie.
Try not to go off on tangents. Keep your focus on your best qualities.
Job Hunting Tips:
"Before you apply, make sure you unearth information about your prospective employer. Understand exactly what they do, their sector, their competition and principles. Stay on top of any issues or news in the sector."