Identify the jacking point of the vehicle. Usually this point is about 12 inches at the rear of the front wheel. You can consult the owner's manual if you are not sure where the jacking point is.
Pay attention to the bodywork condition over the jacking point, be sure that there is no excessive rusting or any other damage that will indicate that the part is weak and may not be able to support the weight of the vehicle.
Position the jack below the jacking point. It must be placed on a stable surface so that the jack will be in a steady position once it is in use. Hydraulic jacks must be positioned on a hard and level ground. A jack placed on an uneven ground can tip over while it is placed under a load.
If replacing a wheel, loosen the wheel nuts before the vehicle is lifted. The car must be in first gear or reverse, or in park if it has an automatic gearbox.
Unlock the locking mechanism on the handle of the hydraulic jack. If not disengaged, the handle can't be pumped, so that jack will not rise.
Re-lock the locking mechanism once the car has been lifted to keep it at the right level.
Use a jack-stand to be placed under the right suspension because you can not rely only on the hydraulic jack to keep the vehicle on its position. The jack-stand will carry the car's weight for effectively.
Reverse the process once the work on the vehicle is done.
Do not overload the jack, or try to lift something that is heavier than the jack's rating as this could lead to an accident.