Over Existing Decking Installation
Existing 2 x 6 cedar deck with roof overhead is good candidate for setting tile over. The wood deck is structurally sound and has a roof to keep most water out.
First set out tiles so that you can pick from different colors to make sure that the tiles are laid in a random color pattern. When laying out deck for tile placement make sure that tile edges align with the joists so two edges of the tile are halfway over both joists. (If the existing decking is a 2” thick then it is not necessary to align tile edges over the joists.)
After establishing the tile layout and setting chalk lines to keep the lines straight, then start setting tile using adhesive. The plastic tile spacers are being used to space the tile above the existing wood decking. The adhesive spots that are applied to the wood will have to be a little bigger to span the gap between the tile and deck.
Plastic tile spacers keep tile spaced above the existing deck so that water doesn't get trapped between tile and wood deck.
Use a 6 ft level as a straight edge to help set tiles straight.
Edge tiles that need to be cut can be cut and set as you go but make sure the bottom is dry before you set with adhesive, otherwise it is probably easier to cut and install the next day.