Short Answer 
To effectively manage Nether portals in Minecraft, players should understand that portal linking is based on a coordinate system, where Overworld coordinates are reduced by a factor of 8 in the Nether. To prevent unintended portal connections, it’s important to keep Overworld portals at least 128 blocks apart by calculating distances and strategically planning their locations.
Step 1: Understand the Linking Mechanism
In Minecraft, Nether portals link based on a specific proximity rule and a coordinate system. When a player enters a portal in the Overworld, the game converts the Overworld coordinates by dividing them by 8 to find the matching coordinates in the Nether. This means that distances in the Nether are significantly shorter, affecting how portals connect.
Step 2: Calculate Distances Accurately
To prevent unintentional linking of portals, it is essential to maintain a distance greater than 128 blocks between Overworld portals. This can be achieved by manually calculating the distances between the coordinates of your Overworld portals. You should follow these steps:
- Determine the coordinates of your Overworld portals.
- Convert these coordinates to the Nether by dividing them by 8.
- Calculate the distance between the calculated Nether coordinates.
Step 3: Strategically Place Your Portals
Control the placement of your Overworld portals to ensure they are at least 128 blocks apart. By doing so, you can facilitate a clear separation between Nether portals. This involves:
- Planning their locations on the map before constructing.
- Using the calculated Nether coordinates to verify the distance.
- Avoiding creating multiple portals within the same small area.