Download the PuTTY installer (putty-0.63-installer.exe) at PuTTY Download Page. (The latest version as of October 2018 is PuTTY 0.70.)
1. Start the PuTTY installer (putty-0.70-installer.exe), then click Next.
2. At the Destination Folder window, select the location for installing PuTTY, and click Next.
3. At the Product Features window, just click Install.
6. After the installation is completed, the Completed the PuTTY Setup Wizard window appears. Click Finish to finish the installation of PuTTY.