Gluing engineered hardwood floors is not a difficult job. If you take your time and have everything ready, you should be able to lay a room in a day. Don't skimp on adhesive, buy a good hardwood floor glue.
Remove the Baseboards
Remove your baseboards as they will not usually be the right height to slide the new floor. Make a chalk line on the floor 31 inches from, and parallel to the longest wall (across the floor beams). Pre-sort the boards according to color according to your likes. You may need to trim the door casing if it will not swing easily over the new floorboards.
If you are installing your engineered floor over tiles, use a grinder or sander to smooth down the surface of the tiles and allow the glue to adhere to them. Sweep or mop up any dirt before filling in any holes or gaps. Vacuum any dust. If you are starting with a linoleum floor, remove the linoleum first.
Nail Down a Straight Edge
Take a straight-edged piece of plywood and nail it into place along the chalk line, on the inside of the line.
Spread the Glue
Trowel glue on a 20-inch strip according to the directions on the adhesive can, using the trowel. Don't spread more glue than you can cover within the open time of the glue or there will be a poor bond. It is better to do smaller areas at a time. If you get glue on your fingers, clean them immediately with solvent or you could get stuck to the wood. It will not come off easily when it has dried.
Glue Down the Boards
Kneeling in the 31-inch area, line up the tongues of the boards against the straight edge. Working from left to right, press the board into the glue. Before you use each piece, discard any ones that are warped or you are not happy with. If necessary, tap the boards into place with a rubber mallet. Make sure you only glue the bottom of the boards, the boards will not fit tightly if the grooves are filled with glue. Don't line up two end splices at the same place, they should be 6 inches apart. Cut the pieces at the end using the miter saw.
Fill the Original Gap
When you have finished the main section, remove the original straight edge and install the flooring to fill the gap. You will now be fitting groove into your tongue instead of the other way round as you work in the opposite direction.
Roll the Floor
There should be a rolling weight value on the adhesive can. It will probably be around 100 pounds. Don't let the glue get too dry before you roll. Rolling seats the wood firmly into the glue and squeezes out blobs; this is difficult if the glue has dried.
Cover the rollers with tape or foam sheets to avoid damaging the floor.