Conventional AP and Anti-Armor mines are emplaced by hand. However, the newer generation of FASCAM (Family of Scatterable Mines) surface mines can be laid by towed trailer and helicopter, such as the Volcano system. In addition, there's the Field Artillery version, which is less accurate and more expensive.
Basically, the FASCAM mines can resemble larger hockey pucks. In the towed version, they are magazine fed through an electronic device which sets the arming and detonating parameters. Then, they pass through a device which is remarkably similar to the thing I used to launch my Hot Wheels cars. The mine rolls between two spinning rubber wheels which launch the projectile. It lands on the ground and awaits a soldier, vehicle, or the preset detonation time. The helicopter system is similar, but an ejection system launches them out of tubes pointing out of a helicopter.
Arty mines are similar, but the projectile is less accurate and efficient. However, you can slap a hasty minefield down in areas where you don't own the land.
The Soviets perfected the "butterfly mine" but the US also uses "toe poppers." Very small, but will blow a GI boot (and foot) to hell.
While "mine-proof" boots may keep the foot in one piece, possibly preventing the need for amputation, the human leg WILL NOT withstand the blast and will break, if you're lucky.