The Box-and-One, also known as the 2-1-2, is a good power play system for spreading out the defense and generating scoring chances from in front of the net. As is the case in most power play formations, your right winger and right defenseman should ideally shoot lefty and your left winger and left defenseman should shoot from the right. Adhering to this rule of thumb will facilitate puck movement as you cycle through the zone.
The Box-and-One power play system is built around your center who plays the mid slot (1). This should be your best all-around player on the ice, someone who is able to catch and dish quick passes as well as place shots accurately on net. Keep in mind that because this system positions your center smack in between most defensive formations, he/she will probably take a lot of abuse regardless of what level of contact you play at. In this power play system, your center should try to keep position in the slot while your team has control of the puck.
Your wingers (2 and 3) set up deep in the offensive zone, hovering between the goal line and the bottom of the circles. This system is going to require these players to work in the corners and along the boards, as well as crash the net hard for rebounds, so they should be able to hold their own physically. Your forwards should be fast enough to chase down pucks deep in the zone and maintain possession, finding outlets at the point, around the boards, and most of all to the slot center. From the corner, your wingers can also walk the puck in along the goal line to put it on net. Even if a shot is from a bad angle, deflections can create many more scoring chances in front of the goal, so take your chances when shooting from inside in this formation.
Defense (4 and 5) play the point. When controlling the puck, they have the option of working it deep in the zone to forwards (2 and 3) or pass amongst themselves hoping to lure defending players out of position. The D should take the shot if they have a clear lane, or feed it to your center hard for a quick shot or deflection.
Point players can shoot more liberally from this formation, because it allows for a greater defensive presence along the blue line. When one of your point players shoots, the other should immediately assume a defensive position in case the shot is deflected by the opposition or they gain possession off a rebound. The shooting player should hold the zone, looking for high deflections and be ready to thwart the opposition from developing a play.