Gluing tiles to a wood floor is generally not recommended because wood floors can be "springy," causing the wood to move when it is walked on. This movement can cause any tiles applied over the wood to shift or crack. Additionally, moisture can get under the tile and cause the wood underneath to warp. However, there is a technique to use that is safe for sticking tiles to wood.
Measure the area of the floor that will be covered with tile. Cut out corresponding sheets of plywood to lay down on top of the existing wood floor. Secure the plywood to the wood floor using the nail gun. Insert a nail into the plywood every 15 cm (6 inches). The plywood will stabilise the floor to keep the tile from shifting or cracking after installation.
Before mixing the adhesive, lay out the tiles on top of the plywood and make any necessary tile cuts or adjustments. Mix the adhesive and, starting in the farthest inside corner of the room, apply the adhesive to the floor. Press each tile firmly into the adhesive and work your way out of the room as you apply the tile. Leave at least 8 mm (1/3 inch) between each tile, to allow for the grout. Let the adhesive set and dry according to the manufacturer's instructions.
Once the adhesive is dry, apply the grout to the spaces between the tiles and allow it to dry. After the grout has dried, the tile can be treated with a sealant or finish.
Always use caution when working with tools.
Mix the adhesive in a well-ventilated area.