The best way to develop your players is to participate in matches and 3D-penalties. That should be done as soon as possible. Experience gain is important for the reason that inexperienced players tend to break rules and get injured much more often. You can set personal tactics for each individual player, also you can manipulate personal pressing and attack sliders for each player – set them to maximum at the 60th minute of the match. The more actions your players perform the faster they gain skills. Until the 60th minute of the match you should stick to default settings. Also remember that the stronger your team becomes the slower your defense line and goalkeeper will gain experience. If the match goes in your favor, move your defense line closer to the midfield and swap their positions.