The Landsat 8 satellite collects images of the entire Earth every 16 days. The data collected by the instruments on board the satellite are available for free download at Glovis, EarthExplorer, or through the LandsatLook Viewer within 24 hours of receipt, can be requested through the pages of the United States Geological Survey (USGS)
Before starting the download you need to have Java application installed, as well as allowing you to browse your access.
As a first step it is necessary to create an account in USGS, some scenes are ready for immediate download; it is also likely that requests can be placed to a list before they are downloaded, an e-mail notification indicates the direct download location, processing usually takes between one to three days, for this it is necessary to fill in the requested data (username availability check, the password must be at least eight characters) from the registration link.
To access you can do so directly with your username and password from the login page.
When clicking on Results, it displays the available Landsat 8 images, then to download the desired image click on the Download Options icon.
A pop-up window with different download options is then displayed, select Level 1 GeoTIFF Data Product (the largest image).
Once you have downloaded the Landsat 8 image, unzip the file (7-Zip, WinRAR, WinZip).