While the skill positions get all the attention, finding success as an offensive lineman requires justas much technique and skill as the more glamorous spots on the field. In addition to being big and getting in the way, offensive lineman need to learn how to block properly before they can every help their team get a win and protect the quarterback.
Proper lineman technique begins before the ball is snapped. It's vital to establish a strong base as a lineman, with one's feet parallel and the weight set back on the balls of one's feet. Most lineman use the three point stance, with the balance hand varying depending on one's position on the line. Assuming one knows the snap count, lineman need to be ready to explode off the line immediately and engage the defensive line, knowing whether to burst left, right or straight ahead.
Once you're ready to go into a block, there are a ton of things you need to focus on or else you may end up flat on the ground. Try to keep your shoulders low and squared with your back erect and head facing straightforward. This will allow you to see the other team's lineman and engage them as successfully as possible. Your power foot will help you keep stable all the way through your body, which you'll plant more forcefully than your second foot.
Keep your base wide and take shorter steps so you won't be caught unstable off the ground. Once you're in the block, thrust your hips forward and push up, extending your arms forward without pulling or grabbing onto the defense. The same is true no matter whether you're in a double block or facing a linebacker. The only variation on this is when you're on the goal line, when you'll generally want to assume a four-point stance, assuming your coach's scheme tells you to do so!