Open command prompt (cmd.exe/git bash)
Recommended:
npm install -g typescript@latest
This will install the latest typescript version if not already installed, otherwise it will update the current installation to the latest version.
And then verify which version is installed:
tsc -v
If you have typescript already installed you could also use the following command to update to latest version, but as commentators have reported and I confirm it that the following command does not update to latest (as of now)!
npm update -g typescript@latest