Centred means placed or situated at the centre. When working with timber, fabric and other materials to create something, the best way to make sure something is centred is by using a centre punch. A centre punch is a tool that is used to mark the centre of an object or surface, usually for drilling a hole.
This web site is under construction but if you want something centred be sure to pick up a centre punch from Bunnings or Mitre 10.