Once you are logged into the app, go to the Search bar and look up your friend. Then tap their name to select them.
From here tap the Write Post icon. You can include a photo, location, or tag friends.
When you’re finished, tap Post in the upper right-hand corner of the screen.
Remember—anything you post on a friend’s timeline can be seen by your friends and theirs. If you’d prefer to share something with them privately, consider sending a Private Message instead.