Place plastic spacers at about 60cm intervals along the longest straight wall and lay the first row of boards with the groove side facing the wall, starting from a corner. The spacers must be wide enough to leave an expansion gap all around the edge of the floor. The ends of the boards are tongued and grooved which are joined by either squeezing a bead of glue along the top of the tongue and groove,but in the main most are click fit nowadays. You will probably need to cut the last board of the row to fit. Mark it with a square or saw, with the finished surface facing up.
Start the next row with the off-cut of the board used at the end of the first row. Always stagger the end joints of adjacent rows by roughly 30cm. Use the fitting tool to push the ends of the boards together as you work. Continue across the room, pushing the rows firmly together and adding more plastic spacers along the two side walls. Force each board together by gently tapping the edge block against the grooved side of the board.
You can either replace the skirting board over the new boards or fix a quadrant moulding over the expansion gap around the edge of the floor. Pin the moulding to the skirting board and paint or varnish.
1) Cutting the boards around door architrave can be fiddly. Instead, saw a piece from the bottom of the architrave, the thickness of the board.
2) Take off any doors before starting work to make the job easier.
3) Leave the opened packs of flooring in the room for at least 24 hours so that the boards can acclimatise before laying, & leave them lying flat,even a couple of hours stood up will warp the shape & make it difficult to fit them together.