I think one of the biggest mistakes made when playing black is to take your eyes off the king. Its easy to be distracted by other things happening, so the king sneaks away!
As white, probably one of the biggest mistakes is to lose too many pieces early on. You have less pieces than black so have to use them strategically.
Maybe one of the better players can go into this in more depth?
(verberg) Als u op uw beurt aan het wachten bent en niet steeds op F5 wilt blijven drukken kunt u ook de pagina snel automatisch laten vernieuwen door op "Verander" naast "Verversen" te drukken op de Hoofdpagina, en de tijd hier in te stellen op bijvoorbeeld 30 seconden. (Servant) (laat alle tips zien)