Match Experience & Player Growth
The amount of game time a player gets directly affects their growth, especially for FC 25 Coins younger players.

Regular First-Team Football
Players who are consistently starting for your first team have the best chance to grow. Regular appearances ensure they gain the experience needed to develop.
Consider giving younger players start opportunities even in tough matches. They can grow faster through experience.
Substitute Appearances and Rotating Players
If a player is consistently being rotated in as a substitute, they may not grow as quickly as a regular starter. However, consistent sub appearances can still help, especially if they perform well and get high ratings.
Loaning Players Out
Loaning younger players to lower-league clubs or other teams where they can get first-team experience is a great way to help them grow. While on loan, players can gain match experience and progress without occupying a spot in your main squad.
Be cautious about loaning players with high potential; a well-managed loan spell can help them reach their potential faster.
Player Growth Through Objectives and Milestones
Achieving objectives and milestones with players can lead to growth. For example:

Players who reach milestones like scoring a certain number of goals or assists, or making key defensive contributions, often see their overall rating improve.
Completing objectives like developing specific skills or performing well in particular competitions can boost player growth.
Potential Drops and Stagnation
Sometimes, a player’s growth may stagnate or drop due to a variety of reasons:
Injury setbacks can delay or stop player development.
Lack of playing time or poor performance on the field can affect growth.
A poor work ethic or negative morale can reduce growth speed, so maintaining a player's happiness is key.
Maximizing Growth for Key Players
To get the most out of your players:

Focus on high-potential players in key positions (e.g., strikers, midfielders, or defenders) who can be the core of your team for many seasons.
Pay attention to player personalities and morale as these factors can impact their training effectiveness.
Don’t forget to rotate your squad to give every player an opportunity to grow, while also managing injuries and fatigue effectively.
Managing Player Decline
As players age, they start to experience decline. This is particularly true for players over 30:

To combat this, you can give older players rest periods to preserve their energy and prevent injuries.
For older players, focus on developing mental attributes and providing them with more specialized roles, like leadership positions, rather than expecting them to cheap FC 25 Coins carry the team physically.