Local Sync - step by step guide for WiFi Sync
Local Sync is installed in PC with Microsoft Windows and Local Sync is installed in Android.
start Windows Local Sync application, open Local Sync application in Android
It is necessary to pair Android with PC otherwise synchronization is not possible, you can start pairing by clicking on button with QR code in Local Sync automatically or do it manually Menu - Pair with PC (in older versions Pair with PC is button with link image; you must provide address and port which is shown in Windows Local Sync in status bar or main log - e.g. if it is shown in status bar http://10.0.2.15:8889 address is 10.0.2.15 and port is 8889)
If QR scan is successful and there is connectivity to the PC (or if pairing was invoked by providing address and port), confirm dialog which is shown in Windows Local Sync
In Windows Local Sync you can select directory which will be root for file synchronization (you can later show this dialog by double clicking on paired PC in Windows Local Sync), press OK button.
In Android you can additionally configure conflict priority, what to synchronize plus directories if you want to synchronize files. Press Save button in the Android.
You can now start synchronization by pressing SYNC! button in Android Local Sync.
Ensure that in Contacts application Local Sync account is visible (Menu - Contacts to display for Android 4.1) and that in Calendar application Local Sync calendars are visible Menu - Calendars to display, if you are new to Android it is the best to have only Local Sync contacts and calendars displayed and not others to avoid confusion
Once PC is paired with Android you just run sync again (i.e. step 6) directly.
Later on, If PC/connection is not available, e.g. IP address changed you need to reconnect paired PC. There are several possibilities:
Initiate QR code scan from Local Sync application to adjust address and port automatically
change address manually - tap on paired PC in Android, press button with link image, adjust settings
in Local Sync in main menu, start pair with PC menu action (or button in older version) and provide address and port