Tongue vs. Groove
Please see the illustration below for an explanation of the tongue vs. the groove.
WHICH WALL SHOULD I START INSTALLING FORMICA ALONG? SHOULD THE TONGUE OR THE GROOVE BE AGAINST THE WALL?
You can start installing your floor against any wall but some are better than others. Typically you want to run your laminate parallel to the main light source to decrease the visibility of the seam across the length of the product. In order to accomplish this you would need to start on the wall either to the left or the right of your main light source. If there is not a large window or main light source we recommend starting against the longest wall.
If all your doors are located on one wall it may be easier to start on that wall so you can slide your laminate underneath the door jams. You will want to start in the left side of the wall you pick with the tongue on the long side of a plank facing the wall. The tongue against the wall should be removed. You can use a sharp utility knife for the 7 or 8mm product but 10 or 12mm will require a saw. It is important to work from left to right to avoid damaging the tongues on the short side of the boards.
I also recommend installing the first and second row at the same time to insure everything is square. Basically what you are doing is using the second row to line up the first row before tapping the end joints together.