Tactical Problem #1: Supporting the player with the ball when in an off-the-ball position.

When in an off-the-ball position, there are some things the player must remember to focus on.

1. Being open to receive a pass from the player with the ball, and therefore help your team to maintain possession.

2. Support the player through defending them from the opposing team that is trying to gain possession.

Here are a couple games to address this tactical problem:

3 vs. 3 - Give and Go

This game can be used for multiple invasion games, soccer being an example. 
To set this game up, split the group into teams of 3 each. Each team will be put against another with a goal line at both ends. The goal is to score a point through passing with your teammates. To achieve this, not only will you have to be aware of your surroundings, but all of the team players who are in an off-the-ball position must find an open area where they can be available to receive a pass and therefore continue to take the ball down the field.

This game also provides an opportunity for off-the-ball practice concerning the opposing team as well. Their goal is to try and take possession of the ball away from the other team to score their own goal.

Keep Away

In the game, a team of two players will face off again another team. The goal is to keep the ball away from the opposing team as long as possible. As an example, I will use basketball.
Set the two teams up in a square, its size depending on how hard or how easy you want to game to be. One team gains possession of the ball and their goal is to try and keep possession until the timer runs out, once again depending on how difficult you want the game to be. To deal with the tactical problem, each player of the team may only hold onto the ball for up to 5 seconds before it must be passed to their teammate. This means that the player off-the-ball must be ready to receive a pass and make sure they are in an available position.
If the other team manages to gain possession of the ball before the timer finishes, they can either begin the timer again and take their turn, or the game can be played as whoever has possession when the times up wins. When the timer runs out, possession is then switched to the opposite team.

 *ɐssılǝɯ*