Plaster the surface of the floor, and it should be completed at least two weeks before laying the tiles.
For fixing floor tiles use cement and sand mortar in the ratio of 1:3, add some water to create a consistent paste.
Soak the tiles in clean water at least for a day before fixing.
Fix the tiles directly from the water as it will get dry once it is kept outside the water for long before fixing.
Maintain a gap of 3 mm between every two tiles.
Wait for 48 hours after fixing the tiles. Then fill the joints with joint fillers. Wipe of excess grout with a sponge.
Special attention should be given to keep at least 6 mm, gap on all sides of floor adjacent to the wall and this gap should not be filled and to be kept completely vacant so as to absorb probable thermal expansion of tiles. However, while fixing skirting this gap will be covered.