This is an excerpt from Football Kicking and Punting by Ray Guy & Rick Sang.
An onside kick can be a surprise kick or a kick that everyone in the stadium knows is coming. The kicking team executes the onside kick with the intention of obtaining possession of the football. An onside kick can be used at any time to create a big play, but usually these kicks are employed when the game is on the line and the kicking team desperately needs the ball in the hands of its offense.
Kicks are considered onside kicks if they go at least 10 yards (enough to be legally recoverable) and provide the kicking team an opportunity to recover the kick and secure possession of the ball. Kicks that can be used for onside kicks include the high-bounce kick, the classic drive kick, and the drag kick.
The high-bounce, or lob, kick is angled toward the sideline, bounces off the ground, travels high in the air, and comes down at a point just beyond 10 yards. This kick gives the coverage team an opportunity to catch the ball before it hits the ground. To get the high bounce, the placekicker positions the football in the same way he normally would tee up the ball for a kickoff, with the exception of turning the tee backwards. This allows the football to immediately hit the ground without making any contact with the tee. He takes a position to the left side of the ball (for a right-footed kicker), about two and a half steps away. From this position, he faces down a line that connects his plant foot, the ball, and the spot he's kicking to-a spot 10 yards away. The approach is similar to that for an extra point or field goal. The placekicker leans, jab steps, steps, and plant steps past the ball, allowing the kicking foot to strike down on the upper third of the football with the inside tip of his toe. He sweeps the kicking leg across his body so the kicking foot doesn't hit the ground or the football as it ricochets upward. This contact forces a quick rotation of the ball into the ground, causing the ball to bounce high into the air as it heads toward its target. Ideally, the football should go at an angle from the tee, gaining distance as it heads toward the sideline to a point 10 yards down field. The football must come down toward the sideline but not too close. It needs to remain in the field of play to ensure an opportunity for the kicking team to secure possession.
The drive kick is one of the most common onside kicks. It has been seen often in the last seconds of a football game when everyone in the stadium knows it is coming. A tee especially designed for this particular type of kick includes a notch that supports the football with its tip on the ground. The placekicker positions the football with the tip on the ground and leans it back on the tee considerably more, presetting the ball in the exact position he wants the ball to travel-angling toward the sideline on a low line and continually touching the ground, causing an erratic skip effect as it travels 10 yards. This kick must be hit with some force to generate the unpredictable motion needed to get results. The objective is for the tip of the ball to hit the ground as it skips, causing the ball to jump up in a split-second, making it extremely difficult to predict or handle. This gives the kicking team time to get in position to recover a mishandled ball or to obtain possession before the return team does. The placekicker aligns the same as he did for the high-bounce kick. The difference is that he strikes the football just below the tip, closer to the center, in order to drive it across the top of the ground. Remember that the tip of the football is touching the ground as the ball leans back and rests on the front of the tee.
Is He Offside?
It might appear that the placekicker is offside when he executes the high-bounce or drive kick because his plant foot is ahead of the football at impact. However, it's understood that a placekicker who's performing a kickoff cannot be offside prior to making contact with the football.
The drag, or dribble, kick is a tremendously effective onside kick that can be used any time. It's especially useful when the kicking team sees that the front line of the return team is vacating their area prematurely in preparation to block. The placekicker positions the football and aligns as he would if he were kicking a regular deep kick downfield. This is one of the main reasons the drag kick can be so effective. Another reason is that the kicker is designated to recover his own onside kick. To be effective, the kicker must appear to be building up speed to drive the kickoff downfield as he approaches the football. At the last moment, as he prepares to swing his leg through to perform the kick, he quickly lifts his leg and simply drags his kicking foot across the top tip of the football. This causes the football to bounce alongside him, traveling at the same speed and just slightly ahead of him as he continues downfield. As he approaches 10 yards downfield, the football is practically waiting for him. All he has to do is recover and down it. The key to this onside kick is for the placekicker to be a great actor and make the kick look like a regular kickoff. This causes the front line of the return team to anticipate a deep kick and quickly vacate the area, allowing the kicker to recover the onside kick untouched. All the onside kicks discussed in this section can take advantage of the element of surprise. The kicker simply aligns as he would if performing a normal kickoff. He then adjusts his steps at the last second and catches the return team off guard.
This is an excerpt from Football Kicking and Punting.