Show your personality ... but not too much. Women in particular can get away with adding a bit of colour to their outfits or accessorising. Make yourself memorable to your interviewer by showing them a bit of who you are. But keep it simple - Marie Claire described the best approach as "colouring within the lines".
It's work, not a nightclub. As Kaye Harding, president of the Northland chapter of Dress for Success says, if you can see up it, down it or through it, don't wear it to work.
Invest in some classic pieces that will tide you through many situations. A good suit in solid, neutral colours can be dressed up or down depending on the season and the event. Spending a bit more money on classic pieces is a good idea because they will last many seasons. A basic suit can be dressed up with an accessory such as a scarf.
Get a manicure. Untidy hands can be surprisingly distracting.
But keep your makeup to a minimum and avoid strong perfume or cologne.
Wear something you are comfortable in, so you can focus on the interview rather than whether your outfit looks right.