Concrete is such a hard and durable substance that it's somewhat ironic that it starts out as a liquid mix of cement, aggregate and water. Once concrete is poured, it needs time to solidify and form solid chemical bonds before it can support weight or withstand force. Concrete is pliable as it dries, so it is preferable for it to dry quickly to avoid damage during the drying process. While you can speed up concrete drying only so much, there are ways of accelerating the process to a certain degree.
Pour the concrete during warmer, sunnier weather. It will dry faster than it would in cooler weather.
Add calcium chloride, an accelerating compound, to the concrete before pouring while it is still wet. Follow the instructions regarding how much to use, but the accelerant can help the concrete solidify significantly faster.
Position a heater near the concrete. This helps raise the temperature and accelerate the drying.
Place a plastic sheet over the concrete to trap escaping moisture. Moisture is important in curing concrete, and the plastic traps escaping moisture to accelerate curing.