When using a floor scraper, you should hold it like you would a long-handled broom or rake.
By running it along the surface of the floor with some force, the floor scraper will separate whatever you are trying to remove from the floor’s surface.
You should hold the floor scraper at a 15-30° angle to the ground as you scrape.
Keep an eye on the sharpness of the blade, and change it once the edge of the blade becomes dull (See: How to replace a scraper blade)
Sometimes, the use of a heat gun can help to soften stubborn glue, making it pliable and easier to loosen from the surface of the floor.
If you do not have a heat gun, you can apply a solution of washing up liquid and warm water to the adhesive instead.