When a kitchen or bathroom faucet loses pressure or starts spraying to the side, it’s usually due to a dirty aerator screen. Luckily, cleaning a screen is an easy job. Start by closing the drain plug (so you don’t drop parts down the drain). Then remove the aerator using a rag or masking tape so you don’t mar the finish with your pliers.
To remove the sand and other deposits, soak the aerator in vinegar, then scrub it with a toothbrush. This usually solves the problem. If you have to disassemble the aerator to clean it, lay out the parts in the order you removed them so you can reassemble them correctly.