Neck, ear or nose hair is distracting and memorable to your interviewers. The night before your interview,mow your overgrown areas. This will leave you looking clean shaven and neat. Brushing your teeth in the morning is not enough. Toss one of those mouthwash bottles in your bag and use it just before you walk I to the interview. The alternative is gum or mint sweets before you enter the building. Just be sure to spit out the gum before you meet and greet.
Since being nervous can release the smelly kind of body odour , the pit swipe is critical. Use a subtle yet fresh cologne which is not overpowering.
Nose blowing can leave traces on your face so triple check. Also dust away dandruff and clear flecks of spinach from your teeth. If you fail in this area your interviewers won’t hear your answers , they will be too pre occupied with being grossed out. Do a last minute check with your phone.
A wet,slimy handshake makes people think of germs and your hygiene. Dry your hands with an alcohol based anyone bacterial lotion. Or you could use an anti perspirant.