Very simple:
- Log into your account and go to the "MY TEAM" page.
- Under the "GAME WEEK 3" icon, click: "MAKE TRANSFERS".
- Click the yellow x box for whatever player(s) you want off your team.
- Click the name(s) of whoever you want to replace the player(s) you just removed.
- Then click the "MAKE TRANSFERS" icon on the bottom left.
- When the next page pops up, click the "CONFIRM TRANSFERS" icon.
Remember you have to have: 2 Goalkeepers, 5 Defenders, 5 Midfielders and 3 Forwards on your team at all times. So, for example, you cannot transfer out 1 Midfielder and replace him with a 4th Forward.
Go back to the "MY TEAM page and if the player you just transferred in isn't in the starting line up, just sub him on the usual way by clicking the yellow icons for who you want in and who you want out. Again you have to remember you can play any formation, but you have to have at least 1 GK, 3 Defenders and 1 Forward on the field at all times.
That should do it. Let us know if you still have problems.