Sit in the car, be calm, take some time to set yourself ahead of entering reception.
Put on a clean suit. Wear it sharp and clean.
Do not use unprofessional terminology.
Make first impressions count and offer warm greetings with all you speak to.
Try not to oversell who you are.
Suggestions for those looking for employment:
"Create jobseeking toolkit and craft job hunting skills. The minute your selected career choices have been targeted, a CV and application letter can be tailored to display your qualities so they match the of prospective employers."