Facebook lets you decide who sees what you post on your wall. It does this through privacy preferences. If you go to the menu with the three horizontal lines, you will find the Privacy shortcuts button.

Privacy shortcutsPrivacy shortcuts

Among the various options is Review a few important privacy settings. Tap on it to see more privacy settings.

Control important privacy aspectsControl important privacy aspects

Since the goal is to control who sees what you share, tap on Who can see what your share.

Who can see what you shareWho can see what you share

Tap Continue to start the privacy wizard.

Privacy assistantPrivacy assistant

First, you have choices regarding your personal information. Adjust these parameters if necessary. To continue, tap on Next:

Control personal informationControl personal information

In the Future posts section, tap on Friends, this is the default option.

Configure who can view your publicationsConfigure who can view your publications

Select who will be able to view your posts from now on.

Privacy options availablePrivacy options available

Repeat the process with Facebook stories tapping on Stories. Similarly, if you want to apply the same restrictions to your previous posts, tap on Limit.

Limit old publicationsLimit old publications

Confirm this last change by tapping on Limit again.

Confirm limitationConfirm limitation

The final step of the wizard will let you block some users. To finish, tap on Next.

Block usersBlock users

With this method, you will have modified the default settings of everything you share. However, you have privacy control in the post editor.

Control who can view a specific publicationControl who can view a specific publication

If you change this setting, the setting will only apply to that particular post. The default settings will remain the ones you chose in the privacy wizard.