When installing a pool in your backyard or anywhere, it is very important to have a level ground. If the ground is not leveled, the pool will not fit and it will stay crooked. If it stays crooked, the water will overflow due to one side being higher than the other side. Ground leveling can be easily done by applying this process. Take two strong stakes opposite each other on any side of the pool. Keep the stakes atleast one foot above the ground. Tie a string between the two stakes and place a spirit level or a carpenter's level on the middle of the string. Move the end of the string according to get at an equal level. Now measure the string to the ground. This is the best way of leveling a ground for a pool.
Don't try to do it yourself, get an expert...
Once you get to the "I think it's level" phase, go to your local tool rental store and get a 360 degree laser level. I have a 27 ft round pool and got it to within 1/2 inch level all around it.
Leveling the ground is quite easy but it requires some tools to perform it. You will need to measure the ground with the help of a spirit level. The spirit level will help you determine the level of the ground. After you have measured the level, it is recommended to get hold of a sod cutter from a local hardware store. The sod cutter will help a lot in leveling the ground. Just follow the instructions. In case you think you cannot do it by yourself, it is also recommended to hire or a rent a bobcat. With its help you will save a lot of time and energy in return of a fee.