FileZilla is a freeware and powerful FTP client for Windows and Unix. It has been designed to be fast and easy to use, with support for many reliable features
First download Filezilla from their official website: http://filezilla.sourceforge.net

When you have it on your computer start the installation.
Just clicking next to the end of the installation will be enough, as the set is to install the program with most appropriate settings.
Once installed, start the program and you will see three text boxes at the top, which you will use to enter your login information. Please enter the following information based on the FTP account with your hosting provider.

Address: (yourdomain.com or the ip address of your server)
Username: (your ftp username)
Password: (your ftp password)
Port: 21

Port 21 is set as default and Filezilla will use it is the standard FTP server port.

When you are ready, press the Connect button.

Now, the connection should be established. On the left of the application screen, you will see an area 'local site'. This area is showing your local computer and you simply can use it as a file manager to expand the directories, find and to choose what you wish to upload.

On the right side of the screen you will see the 'Remote Site' section. This will represent your account on the remote hosting.

To upload files from your local computer to the remote host, simply select and drag the files from the 'Local Site' Section and drop them to the 'Remote Site' directory that you wish. Other option is to put files in a queue as dragging them to the queue panel. When you are ready to transfer them, just press the 'Q' button with the arrow at the top.

The transfer queue window will show you the progress of the files upload. Multiple files may be uploaded simultaneously and will transfer at different rates, depending on the file size and the internet connection you have.

If you want to download files from your hosting, just do the opposite.