After sharpening both sides of the blade place it on the kits cone-shaped balancer. If one side dips below the other continue sharpening it until the blade rests level. Return the sharpened blades to the mower and reattach. If you have a torque wrench its a good idea to use it here. Often you need to tighten the blade mounting bolt/bolts to a specific tightness level. Typically measured in pound-feet your instruction manual should list these specs. For example my personal machine the Honda HRR216VKA between 36 to 43 lb-ft of torque is required.
In the following guide we mainly focus on walk-behind mowers since the majority of lawns are served perfectly well by these machines. However if you have a lawn that is larger than half an acre you may want a riding mower. If you have a yard that is between a quarter and half an acre consider a self-propelled model. This basically means you do less pushing. Self-propelled mowers are especially helpful on hills. Also pay special attention to blade size. Look for a mower with a blade thats at least 20-inches long if you have a larger yard. Conversely if you have many narrow areas to mow a smaller deck the area within which the blade spins around is best.
With the mower still on its side grab your socket wrench and wood block. Place the block inside the blade well. This is to prevent the blades from turning while you loosen their bolts. Remove the blade mounting bolt/bolts. A typical mower will have one blade like the Craftsman 37700 I serviced for this guide (one mounting bolt). Some like my Honda HRR216VKA have two blades an upper and a lower (two mounting bolts). Each blade should have at least two cutting edges.