To install node version manager, go to

http://nvm.sh

Follow the instruction. Always refer above site for latest version.

curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.33.2/install.sh | bash

Now you need to close terminal, reopen.

root@hon-vpn:~# nvm

Node Version Manager

Note: <version> refers to any version-like string nvm understands. This includes:
  - full or partial version numbers, starting with an optional "v" (0.10, v0.1.2, v1)
  - default (built-in) aliases: node, stable, unstable, iojs, system
  - custom aliases you define with `nvm alias foo`

 Any options that produce colorized output should respect the `--no-colors` option.

Usage:
  nvm --help                                Show this message
  nvm --version                             Print out the latest released version of nvm
  nvm install [-s] <version>                Download and install a <version>, [-s] from source. Uses .nvmrc if available
    --reinstall-packages-from=<version>     When installing, reinstall packages installed in <node|iojs|node version number>
    --lts                                   When installing, only select from LTS (long-term support) versions
    --lts=<LTS name>                        When installing, only select from versions for a specific LTS line
  nvm uninstall <version>                   Uninstall a version
  nvm uninstall --lts                       Uninstall using automatic LTS (long-term support) alias `lts/*`, if available.
  nvm uninstall --lts=<LTS name>            Uninstall using automatic alias for provided LTS line, if available.
  nvm use [--silent] <version>              Modify PATH to use <version>. Uses .nvmrc if available
    --lts                                   Uses automatic LTS (long-term support) alias `lts/*`, if available.
    --lts=<LTS name>                        Uses automatic alias for provided LTS line, if available.
  nvm exec [--silent] <version> [<command>] Run <command> on <version>. Uses .nvmrc if available
    --lts                                   Uses automatic LTS (long-term support) alias `lts/*`, if available.
    --lts=<LTS name>                        Uses automatic alias for provided LTS line, if available.
  nvm run [--silent] <version> [<args>]     Run `node` on <version> with <args> as arguments. Uses .nvmrc if available
    --lts                                   Uses automatic LTS (long-term support) alias `lts/*`, if available.
    --lts=<LTS name>                        Uses automatic alias for provided LTS line, if available.
  nvm current                               Display currently activated version
  nvm ls                                    List installed versions
  nvm ls <version>                          List versions matching a given <version>
  nvm ls-remote                             List remote versions available for install
    --lts                                   When listing, only show LTS (long-term support) versions
  nvm ls-remote <version>                   List remote versions available for install, matching a given <version>
    --lts                                   When listing, only show LTS (long-term support) versions
    --lts=<LTS name>                        When listing, only show versions for a specific LTS line
  nvm version <version>                     Resolve the given description to a single local version
  nvm version-remote <version>              Resolve the given description to a single remote version
    --lts                                   When listing, only select from LTS (long-term support) versions
    --lts=<LTS name>                        When listing, only select from versions for a specific LTS line
  nvm deactivate                            Undo effects of `nvm` on current shell
  nvm alias [<pattern>]                     Show all aliases beginning with <pattern>
  nvm alias <name> <version>                Set an alias named <name> pointing to <version>
  nvm unalias <name>                        Deletes the alias named <name>
  nvm reinstall-packages <version>          Reinstall global `npm` packages contained in <version> to current version
  nvm unload                                Unload `nvm` from shell
  nvm which [<version>]                     Display path to installed node version. Uses .nvmrc if available
  nvm cache dir                             Display path to the cache directory for nvm
  nvm cache clear                           Empty cache directory for nvm

Example:
  nvm install v0.10.32                  Install a specific version number
  nvm use 0.10                          Use the latest available 0.10.x release
  nvm run 0.10.32 app.js                Run app.js using node v0.10.32
  nvm exec 0.10.32 node app.js          Run `node app.js` with the PATH pointing to node v0.10.32
  nvm alias default 0.10.32             Set default node version on a shell

Note:
  to remove, delete, or uninstall nvm - just remove the `$NVM_DIR` folder (usually `~/.nvm`)

root@hon-vpn:~# 

Install Latest Stable version of node.js

root@hon-vpn:~# nvm install stable
Downloading and installing node v8.1.3...
Downloading https://nodejs.org/dist/v8.1.3/node-v8.1.3-linux-x64.tar.xz...
######################################################################## 100.0%
Computing checksum with sha256sum
Checksums matched!
Now using node v8.1.3 (npm v5.0.3)
Creating default alias: default -> stable (-> v8.1.3)

Setting Default Node version

root@hon-vpn:~# nvm use stable
Now using node v8.1.3 (npm v5.0.3)
root@hon-vpn:~# node --version
v8.1.3
root@hon-vpn:~#