Visual Studio includes a batch file that prepares the environment for you (actually, the Developer Command Prompt calls it under-the-hood).
I've never tried with the Community Edition, but for VS 2017 Professional it is located at "%ProgramFiles(x86)%\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\vcvars32.bat". It may vary if you changed the installation path, of course.
So, all you have to do is to invoke it:
call "%ProgramFiles(x86)%\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\vcvars32.bat"
Something like following should appear
**********************************************************************
** Visual Studio 2017 Developer Command Prompt v15.7.3
** Copyright (c) 2017 Microsoft Corporation
**********************************************************************
[vcvarsall.bat] Environment initialized for: 'x86'
After that you can invoke cl, nmake, msbuild as within cmd.
You can also invoke vcvarsall.bat x86 instead (the vcvars32.bat is just a shortcut for that).
You can avoid typing it each time by creating a batch that automatically invokes it and then open a command prompt
call "%ProgramFiles(x86)%\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\vcvars32.bat"
cmd
And then run that batch instead of cmd.
Another option is to add the "%ProgramFiles(x86)%\Microsoft Visual Studio\2017\Professional\VC\Auxiliary\Build\" to the path so you only have to type vcvars32.bat when you need the developer tools.