Concrete pour tips
Finish-trowel the surface after the water on top disappears
If you trowel concrete too soon, too much cement (paste) will rise to the surface, weakening the surface layer. But once the concrete begins to firm up and the water disappears, be prepared to move quickly with your troweling. Concrete can harden fast.
Cut control joints about 1 in. deep
Control joints should be cut about one fourth the thickness of the slab during the finish-troweling process. Concrete shrinks slightly as it cures and will crack at regular intervals. You want the cracks to occur at the control joints. Space the joints about every 4 ft. on walks and at least every 10 ft. on larger slabs. If the concrete hardens before you can cut the grooves, cut them the next day with a circular saw and diamond blade.
Keep the concrete damp for a week
Concrete will cure harder and stronger if it has a chance to dry slowly. In cool and moderate conditions, cover it with plastic. Under hot conditions, above 80 degrees F, frequently water it down with a garden hose to keep it moist. If kept wet, concrete will reach about 90 percent of its maximum strength after about a week.