First is to download the software :

The very first time you use Duplicati, you will be greeted with a special page.

On this page you must select the "Setup a new backup" option. If you loose your data or your machine later, you can restore the setup, by selecting the "Restore settings from a previous Duplicati installation" option.

If you start the wizard again later, you will see the normal setup page.

On this page, you must select the "Schedule new backup" option, and then click "Next >"

In the "Name" field, you can enter any name you like for your backup. Choose a name that describes what the backup is about, ea.: "My text documents".

If you plan on adding many backups, you can arrange them into folders. To do so, click the "Add Folder" button, and give the folder a name. You may drag-n-drop folders to further structure your backups.

When you are done, click the "Next >" button.

If you want to backup your documents, check the appropriate boxes. Note that you cannot backup files across drives, so if your machine has multiple drives, you may not be able to backup everything in a single backup. Duplicati will inform you if your selection is invalid.

If you want to specify exactly what folder to back up, check the "A specific folder" radiobutton. Then click the browse button ("...") and select the folder you wish to back up. Duplicati will calculate the size of the files in that folder.

Duplicati will attempt to calculate the size of the files that will be backed up, so if you wait a little, you can see this a the bottom of the page. The actual backups are usually smaller, because the files are compressed.

When you are done, click the "Next >" button.

If you store your backups, there is the posibility that someone will read it. This is especially true if you do not own the server where you store it. Even if you own the server or disk where it is stored, it could get stolen.

To protect against other people reading your backups, you can encrypt the backups. You should choose a passphrase that is both long and hard to guess. The button "Generate password" will generate a strong password for you. Be sure to keep a copy of the password. No one can restore your backups if the password is lost!

If you prefer, you can use the GnuPG program to encrypt data, rather than the built-in AES encryption. On the very first run, Duplicati will automatically check the option to use the same settings on subsequent backups.

Even if this step seems difficult, it is very important that you enter a password AND WRITE IT DOWN!.

When you are done, click the "Next >" button.

On this page you must select where to store the backups.

In the server field, you must enter the hostname of the server that will store the backups. In the path field, you can enter the name of a folder where the files will be stored. The username and password field are used to log into the server. If you use passwordless login (eg. by using pageant on windows), remove the check mark for the password. The port is usually the default 22, but may be changed.

All the information required on this page should be avalible from the SSH service provider.

The test button will test the connection, and thus reduce the chance that the information contains errors.

When you are done, click the "Next >" button. If you have not already tested the connection, Duplicati will ask you if it should be tested before you continue.

On this page you can choose to display pages with some of the more advanced options that Duplicati offers. You are free to ignore this page entirely, and just click next.

For the purpose of this guide, I will check all the boxes, and walk through the entire guide.

If the last checkbox is checked, Duplicati will add the entire setup database to each backup. This will make the backups slightly larger, but if you loose all your data (eg. the machine is stolen), you can simply point Duplicati to the same place, and it will restore all the settings.

When you are done, click the "Next >" button.

In the fields "Run the backup at this time", you may enter the time when Duplicati should run your backups. You can use this to start the backups at a time when the computer is on, but you are not using it. If you work at an office, you could select the time when you are out to lunch.

It is very important that backups are always up to date. There is no point in having a backup from last year, if you need the file you edited yesterday. In the "Repeat the backup regularly" you can enter how often you want the backup to automatically run.

You can choose one of the predefined intervals, or enter a custom interval. The syntax for custom intervals is a bit special, but easy to learn. If you want to backup up every day, enter "1D" for one day. You can also enter "3M" for each three months. You can even combine them with "1M3D" or "14D1M". You can use "Y" for years, "M" for months, "W" for weeks, "D" for days, "h" for hours, "m" for minutes and "s" for seconds.

The setting you choose depend on how often you modify the files. A common setting is "Each day" (1D), which is also the default.

When you are done, click the "Next >" button.

Each time you make a backup, only some of the files are changed. Duplicati can detect what files (and what part of the files) are changed, and only backup the changed portion. This makes the backup take up much less space and run much faster. This type of backup is called an incremental backup.

Too many incremental backups can make the system slower, because it has to look back into all the partial backups to locate a single file. For this reason there should regularly be created full backups. If you select the default of 4 full backups, Duplicati will automatically remove backups older than the last 4 full backups. If you have a full backup each month, you can recover documents from as far back as 4 months.

Instead of counting the number of full backups, you an enter how old data you want to keep. If you want to be able to read data as it was 2 years ago, you can enter "2Y" in the "Never keep backups older than this".

You can use both clean up methods, but this is not recommended.

When you are done, click the "Next >" button.

That was all!

Review the settings to see that they match your expectations. Click finish when you are done, and the backup will be added.

If you want the backup to start immediately after adding it, check the "Run backup now" box.

When you are done, click the "Finish" button.