1. If you wear a suit to work then make sure you have a navy and a charcoal first before any other colours. Patterns and stripes will be memorable but with plains a different shirt and tie and they whole look is changed.
2. Always have your tie done up - The idea that an undone tie makes you look hard working is bull. Look professional and always ready to meet prospective clients, bosses, emloyees, etc.
3. Every time you leave your desk put on your jacket - if your bosses or clients happen to see you then they see you always looking sharp and ready to meet someone. They'll love it.
4. Polish your shoes at least 1 a week - more is better but this is the very least. If your clients or employers see you can't take care of your own shoes then how can they expect you to look after their business?
5. Shave properly - if you have a beard then trim it and keep it looking professional. If not then shave daily. Don't let a growth appear until you have a holiday.
6. Don't eat smelly foods - this is part of your appearance as it can completely base someone's first impression. What if you met you new super wealthy client who has trusted his business' welfare with you for the first time and you have stinky garlic hummus breath. Silly huh. Always have mints in the pocket of your jacket. This goes especially for smokers.
7. Keep those fingernails short and clean - keep a nail trimmer at work for those days you have forgotten and need to trim or at least clean. Keep in desk drawer. Can you imagine shaking you new bosses hand who you hoping for a promotion from and you have nails with tons of dirt underneath? And trust me, the other person will always notice if their dirty. Sod's law.
8. Try to let your suits hang for at least 4-5 days between wears - this lets them relax naturally and help lose those cemented wrinkles. This will also mean you can dry clean less which is better for suits as the chemicals kill wool.
9. Treat your skin well - use moisturisers and products to keep your skin in peak condition. Your clients, colleagues and even maybe that girl you really like will spend a lot of their work life really close to you so make the view good looking for your sake.
10. The most important of all. The must of all musts. Bathe twice a day and use deodorants afterwards and have spare in the office. interviewed a great chap recently and was a wonderful guy with tons of spirit and drive. Real potential but sadly had bio. And whilst I am sure we will hire him the thought does cross your mind that you may have to work with his guy for many years. And when you got two guys who are as skilled as each other, hey why make the employers decision easy by smelling to high hell?