- 1). Open the 7-Zip file manager, and navigate to the file you want to compress.
- 2). Right-click on the file and select "7-Zip"; then select "Add to Archive."
- 3). Select the archive format. You can choose from .zip, .7z and .tar, among others.
- 4). Move down to the compression level section; then select the compression ratio. Choose "High" or "Ultra" to use a high compression ratio.
- 5). Click on "OK" to compress the file with a high compression ratio.
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