Oftentimes, when a faucet begins to run slowly or pressure is poor, it is due to a clogged aerator. Many aerators can screw right off the front of the faucet. some require special tools provided by the manufacturer.
if you need some extra help getting the aerator off, a pair of pliers works great. One tip to save the finish from scratches is to wrap the jaws of the pliers in electrical tape!
If the parts are looking worn out, this is an inexpensive part to replace.
If the parts look okay, but dirty, grab and old toothbrush and scrub them down!
our friends at The Family Handyman have this great diagram of all the parts of an aerator. make sure you don’t lose any parts!