The first step would be to choose and decide how big your area is going to be. Once this is done you can call your local plumber, electrician and such to see if there are any wires or pipes that are in the area you are planning to work in. This is just a precaution for the safety and to save you money by avoiding any problems. If everything is safe and ready then you can beging to dig down below the root level of vegetation in the area, a good fifteen cm or so, this is so you can find dry soil. Once you have done this over the whole area water it and let it dry overnight, this will make digging easier.
Use landscaping cloth to create a barrier between the old soil and the new soil that you are going to be using, this will create a barrier between unwanted weeds and other unwanted vegetation that could grow in your patio. You lay down the new dirt and try and flatten it as much as you can, there are a few machines and tools that help with doing this these are wacker plate compactor or tamper. After you have laid down you bricks it is crucial to have a strong edge, this is usually a cement or vinyl edging (speak to proffesionals for help). When working always keep a few bricks or paving on hand, this is so if there needs to be any repairs there are spairs to cut and fit in spaces.