Unload all of your stone and store it in a dry place. Stone should always be stacked upright taking care to protect the edges – use softening material e.g. dry timber battens, polystyrene or underlay to place it on.
The tiles should be clean and dry before you start. Laying damp tiles is not a problem in itself but the presence of moisture will affect the colour of the stone. Damp tiles will appear different to dry ones. The tiles may need to be cleaned as it is common for them to be packed wet and in some cases residues from the cutting process will need to be washed off with clean water. Start the work only when all the stone is on site. Mix the stones from different crates to insure the natural variation is evenly distributed across your new floor.