It has always amazed me that computers, unlike almost every other piece of household equipment, are generally sold without any maintenance instructions nor, indeed, any indication that maintenance is necessary. This page describes a few hints-and-tips, second-nature to "techies", to help you maintain your Windows-based computer in the best possible condition.
Some may regard these recommendations as "overkill" for a new computer with a decent amount of RAM and a large hard disk, but they will certainly maintain the performance of an ageing computer, or a hard disk that is getting full.