You apply the PVA mix wet with a roller or brush, when dry (usually in a hour or so, although best to leave longer this time of year) it should feel slightly tacky, this is what gives the 'bond' for the tile adhesive to stick to. With tiling you are introducing very visible horizontal and vertical lines, so setting-out is critical if you want a professional looking finish. Work out beforehand where tiles will be positioned and how they will line up with features e.g. cabinets, cooker hoods, sockets etc. If you have a strong focal point such as a hob/extract hood, use this as the vertical setting-out point, either centring the tile or the tile joint on the middle of the hob. Don't start with a full tile in a corner, like the worktop it might be out of plumb. Cut tiles work best in corners...