The premise of this guide is to provide you, a simplistic approach on how to use Opposition Instructions (OIs) effectively.

I'm going to be going against a future Chelsea (2029) squad who are currently still pretty strong.
(Below is from the Scout Report, knowing the roles helps a little too, however, this may not marry up to the line-up you're against so always worth checking the OIs within the match).

Tight Marking
Used to prevent the opposing player(s) from getting the ball, or restricting their movement on the ball.

Always

• Creative players are always a target to be tightly marked. Look for opposing players that have high attributes in Crossing, Long Shots, Passing, and Flair. If you can prevent these types of players from getting the ball or having to move out of position to receive it, you're preventing them from being that creative force.
• Isolated players. Again, this will depend on their attributes but good examples of this is a lone striker, or marking a DM with your AMC and vice versa. Taking them out of the game can lead to more interceptions and more chances for your own team.
• It is also important to note, not to overdo tight marking as it will and can impact your team shape and you do have to pay attention to what the opposition does during a game. They will change formation, player positions and of course substitutions.
• Lastly, it's worth thinking about the player that will be marking them. No point trying to use someone to tightly mark, who is very poor at Marking.

For my example I will be marking Arthur, he's playing as a Deep Lying Playmaker for Chelsea, and has some amazing creativity. If I can stop him receiving the ball and being able to ping it across to the others, seems like a good start. Plus, he's slow, so a very good example.

Never

• Fast, pacey, good at dribbling, very mobile players. Those that have high Dribbling, Acceleration, Agility, Pace, and the Knocks Ball Past Opponent PPM. As soon as they get the ball, they'll beat the marker. Whereas if they were stood off him, they have a bit more time to get the tackle in.
• Also, be wary of the Tries Tricks PPM as that can also lead them to beating their marker.
• The players that you don't mind getting the ball. For example, those less creative/no-nonsense players.
• Generally, I never, use never except in very rare cases.

Pressing Intensity
When not in possession, players hunt the ball to re-gain possession almost immediately after losing it.

Always

• Indecisive players that aren't quick or good at dribbling. Players that have low Dribbling, Bravery, Composure, and Decisions. This will lead to that player often being pressured into a bad pass or shot.
• DMs are naturally a good choice to close down as they are often a linchpin for an opposing side.
• If you notice an opposing player is "Nervous" during the match, change your OIs and press them. Force them to make mistakes.
• Players that have PPMs like "Dwells on Balls" and "Stops Play" are also very good targets to press.
• Like tight marking, don't overdo pressing at it will impact your team shape.

As you'd expect from Chelsea, they don't have many players that are very indecisive, however, I have found a weak link. 31-year-old, Theo Hernandez!

I am hoping my AMR will put him under enough pressure that he never really gets to have a free run.

Never

• Agile, mobile players, that have high Dribbling. As soon as your guy goes to press, they'll get around them like there is no tomorrow.
• AMCs, they are usually more technical and have high dribbling, making the press on them risky as it'll likely be your DC that pushes them.
• Similar to the “Never Tightly Mark” instruction. I never, use never except in very rare cases.

Tackling
To dispossess the ball from the opposition.

Hard

• Players that have low Bravery, and Tackling. LiamH talks about it well. Essentially on a 50/50 challenge, the opposition player will jump out of the way, or the opposing player will double-foot your player leading in yellows/red cards.
• Tired and injury-prone players are also good candidates. If you can completely take out an opposing player, only a win for you right?
• An isolated striker, that is playing in a defensive setup to limit his involvement in the game.

Here's a prime example of a good player to go hard on...

Normal

• I never use "Normal Tackling". Seems a bit useless but it can have its circumstance:
• E.g. If using the team instruction "Get Stuck In" you can alter it for that particular position.

Easy

• Players that have high Dribbling, Acceleration, Agility, and Pace. Essentially if you went in hard on them, they will get the foul.
• An isolated striker in a more attacking/aggressive system. As this will prevent him winning a penalty of free kicks in dangerous positions.

In this case, I am going to take it easier on Phil Foden, going hard on him isn't really going to gain my anything due to his attributes.

Show onto Foot
This will require you looking at the preferred foot of each player and their positions:

Show onto Left/Right-Foot

• Players that have the preferred foot as Right-Only, then Show onto Left-Foot.
• Players that have the preferred foot as Left-Only, then Show onto Right-Foot.
• Useful against wide-players:
• Showing an AMR Inside Forward onto their right-foot can prevent them from doing the Robben-esque cut-inside as it will push them out wide.
• Showing an AMR Winger onto their left-foot can prevent them from doing Beckham-esque crosses as it will push them in narrower.

Show onto Weaker Foot

• Essentially the same as the above "Show onto Left/Right-Foot but more automatic.
• Useful for setting static OIs that aren't dependant on the player but the position.
• Generally used on more central players like CMs and DMs.

There's also another way to decide this taking from an theorem by wwfan in 2009.

• Slow striker(s) with good Jumping Reach and Heading and bad Acceleration, Agility and Pace (Peter Crouch).
• Allow the wider players to go inside.
• Fast, shorter, mobile striker(s) that have good Acceleration, Agility, and Pace but bad Jumping Reach and Heading.
• Force the wider players outside.
• Fast, and tall strikers.
• Show the wider players onto their weaker-foot.

Sadly, this Chelsea team doesn't have any players that are "only-footed" players, and even though the scout report states the AML/AMRs are Inside Forwards, the right footed-player is in the AMR (Pulisic) and the left-footed player is in the AML position. Their striker is also very well rounded. That won't stop me. I'll show their DL/DR onto their weaker foots.

Specifically Theo, again... I want him to have a bad game and not to putin crosses from outwide with his left foot, plus I intend to exploit him.

Finished Product
So using all of the above, this is how I intend to use the OIs against Chelsea:
(You'll notice the line-up doesn't quite match that of the scout report, it's why it's always important to check the OIs in the actual match itself)

Both the LB and RB of Chelsea had a nightmare of a game! Arthur/Roca was to, until they got the assists to Dubos which was my mistake. I didn't adapt well enough and they got two balls over the top for Dubos to put away easily.

Overall, I'd say that was a success! We achieved what we wanted, and we got the 4-2 win. Still think it should have been 4-0... or at most 4-1.

Remember, adapt during the match! Teams will make subs, change mentality and shape! You need to adapt to them on the fly. Don't make the mistake I made!

Other Guides:
Finding Your Voice! A Simplistic Approach To Shouting