Old and worn concrete can become dull, grey and unattractive. Wear and tear from cars causes cracks, then water seeps into those cracks, which can make them worse in cold weather. You can always pay someone to resurface your driveway, but why do so when you can resurface it yourself?
Use your hose to wash down the entire driveway surface, focusing particularly on spaces between any cracks. Let the driveway dry completely.
Use concrete filler within the cracks, then sand or scrape down any excess filler to make it even with the rest of the surface. Let the filler harden completely.
Take your concrete mixer and combine it with a generous amount of water. You'll want the mix to be runny and watery as you are only using it to go over already existing concrete--you are not pouring a new concrete driveway.
Use your shovel to place a one to two-inch layer of concrete over the top of your driveway. Use the concrete trowel to even it all out as you go along. You may want to perform this step in smaller sections--shovel out the concrete and trowel it smooth in one small area, then move on to the next area until the entire driveway is completely resurfaced.
Let the new layer dry for approximately 24 hours, then sweep any debris or dust and hose it down.