The drill we use is as follows;
1. Lead man comes under contact, drops to cover, and engages. Immediately the rest of the element splits left and right 2 paces.
2. The lead man withdraws through the opening left giving the #2 man a slap on the shoulder as he passes indicating that the #2 mans arcs are clear, and so on through the element.
3. When the #3 man hears the firing up front and after moving off the path he prepares a smoke or WP grenade, when he sees #1 move through #2 he throws the grenade and prepares his weapon to fire to cover #2 when he moves through.
4. The #4 man if so equipped prepares his Claymore or other IED and sets the fuse, when #3 has withdrawn through his position he fires and pulls the igniter.
The #1 man will determine the length of each bound by setting up to cover each man as they pull back. After 1 or 2 bounds (depending on the terrain) the element moves into an extended line formation and conducts the withdrawal back to the last RV point by pairs fire and movement or can set up hasty ambushes on the enemy if they are still advancing. This drill takes a lot of practice to be done correctly.
With a 2 man element it is better to withdraw by bounds firing only enough rounds to keep the enemies heads down. Firng off of a full mag takes too much time and slows the rate of withdrawal down. The drill must be practiced to include wounded members and stoppages of weapons.
Practice this tactic with your unit at your next FTX. Start out with a "Dry Fire" exercise. When you have the movement down, train using .22 caliber weapons. When you feel your unit has the procedure down pat, train using your Main Battle Rifles.