Mix the Quikrete in a wheelbarrow using a mixing hoe. Add 5 gallons of water to the wheelbarrow before adding the concrete mix. Wear a dust mask to prevent inhalation of the dust. This dust is caustic and will harm the lungs. Add the Quikrete slowly, stopping and mixing small bits as you go. This will help keep lumps out of the Quikrete and make the mixing easier. Make your mixture a little wet rather than dry so that you will have enough time to work with the concrete. Soup is the desired consistency.
Pour the concrete mixture into the footer and work it around in the footer with a hard rake. Push the Quikrete across the footer, raking it out level and even. Work the Quikrete up and down with the rake to force the gravel to the bottom of the mixture, bringing the concrete mud to the top. Do not rake the concrete out too thin as this will dry out the mixture quicker. If you will require extra concrete, use a board to hold off the concrete in the footer, preventing it from spreading too thin in the footer bottom.
Smooth the Quikrete out with a concrete trowel once the footer has been filled. Rub the mixture vigorously to bring the concrete mud to the top. Wet the concrete lightly with a garden hose to prevent it from drying out prematurely before you can get it down and smoothed. Quikrete has an excess of sand in the mixture, so pay special attention to the sand on the surface of the concrete. If the sand begins to appear in the mixture, mix the concrete around with your trowel to achieve best results.