What's the least painful way to improve water pressure in my house?

fine for a week then dropped again points at something clogging, not the supply. unscrew the tap aerators (usually full of grit), take the shower head off and soak it, and if there's a whole-house filter, swap the cartridge. check the main stopcock is fully open too, they get nudged. if every tap is equally bad and the stopcock's open, the pressure reducing valve on the incoming main may be on its way out - plumber job, but not a dear one.