To create a line-up for a match, go to "My matches" and click on this icon:
You will now be on a page where you can drag your players from the left to a position on the field on the right.
In the top left of the field you can select the formation you want to play, for example 4-4-2 or 4-3-3. Depending on what you select here, you'll see a number of grey locations to drag your players to.
You are not limited to these locations, you can also drag your players to the dotted locations that are not part of the default line-up if you want make custom adaptations. Just make sure you have 11 players on the field, and have exactly 1 keeper and at least 2 defenders, 2 midfielders and 1 forward.
By default, your lineup is only saved for a single match. If you select a save-slot before clicking "save" then the line-up is saved under that slot. You can then load that line-up for future matches as well.
Below the field there are 6 fields available for substitutes. These players won't be in the starting squad, but can be substituted during the match. When a player is injured, an automatic substitution will be made with one of these players.
You can also program substitutions by clicking the substitution icon next to one of the substitutes and selecting a player and minute for the substitution. Keep in mind that during a match only 3 substitutions may be made per team.
You can add additional conditions for a substitution, like "my team is ahead" or "my player got a yellow card". When you do this, the substitution will be executed only when this condition becomes true at any time after the minute specified for that substitution.
Finally, you can specify that the new player will play on a different position on the field than the one he replaces. When this field is left empty, the new player will take over the role of the old player.
You can click the "auto" button to let your assistant create a line-up. You can then adapt the line-up or just play with the line-up created by your assistant.
Players that are injured or suspended can't be selected in a line-up. If a player gets injured or suspended after you created a line-up, the line-up icon for that match will change to a red cross. You can correct this line-up manually. If you don't change an invalid line-up before the match starts, your assistant will fill in the empty spot.