You don't have to take any precautions, like an uninstall of a previous version, when installing a newer version. If the newer version you are installing is from the same release (i.e. same major/minor version), it will replace your previous installation. If it is from a newer release, it will install side-by-side, and keep your previous installation as well.
Notes - If you are installing a newer version of the same release, this will remove the previous installation and overwrite it with the newer one. In case you want to keep a backup copy of the original installation, you can manually make a copy of the installation folder, before installing the newer version.
