GIMP (Gnu Image Manipulation Program) is a free open source alternative to Photoshop and is available for all operating systems. You can download GIMP from the developer site. GIMP installation is very similar to most other programs.
Steps
Method 1 of 3: Windows
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Step 1. Download the GIMP installer
You can download it for free from gimp.org/downloads.
Click on "this link" to download the file. Clicking "Download GIMP" will download GIMP using BitTorrent
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Step 2. Launch the GIMP installer
It is located in the location where it was saved, usually in the download / My Downloads folder.
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Step 3. Follow the instructions to install GIMP
Most users can leave the default settings.
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Step 4. Finish the installation
After selecting the file formats, install GIMP. This may take a few minutes.
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Step 5. Start using GIMP
Once GIMP has finished installing, you can start using it. Check out the guide for tips on getting started.
Method 2 of 3: OS X
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Step 1. Download the GIMP installer
You can download it for free from gimp.org/downloads.
Make sure you download the latest "native" version available
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Step 2. Open the DMG file
You can find it in the Downloads folder. When opening the DMG file, you will see the GIMP icon.
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Step 3. Drag the GIMP icon to your Applications folder
Wait a few moments while the program is copied.
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Step 4. Open GIMP from the Applications folder
If you get a message informing you that GIMP cannot be opened because it was downloaded from the Internet, read on.
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Step 5. Click on the Apple menu and select 'System Preferences'
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Step 6. Open the "Security & Privacy" option
At the bottom of the window, you should see a message indicating that GIMP has been blocked.
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Step 7. Click on
Open anyway.
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Step 8. Start using GIMP
Once GIMP has finished installing, you can start using it. Check out the guide for tips on getting started.
Method 3 of 3: Linux
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Step 1. Launch the packet manager
GIMP can be downloaded via your Linux distribution's packet manager. This utility allows you to search, download and install new Linux programs.
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Step 2. Search for "gimp"
It should be the first result that appears in the search.
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Step 3. Click on the "Install" button
GIMP will be downloaded and installed automatically.
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Step 4. Launch GIMP
You can find GIMP in the Applications folder. Double click on it to get started. See the GIMP user guide for further advice.