Guide to switch from Visual Studio to Emacs on windows?

You'll need to consider whether you want to use Emacs as your editor only, but continue to maintain your project settings, source files and build/debug environment in Visual Studio, or switch completely to Emacs as you editor and use some other tools (e.g., make) to build your project using VS compilers or other compilers completely.

The former case is relatively easy - you can have your file open in Emacs, and the project open in Visual studio, and just Alt-tab over to VS to build and debug. There are a couple good ports of graphical Emacs for Windows, or you can just use Cygwin combined with the terminal version of the application.

The second option - switching to a fully UNIX-like build environment is more involved and extends far beyond what editor you will be using.

Update, given comment below on "baby steps":

If your goal is to get to a complete non-VS (with the possible exception of the actual compiler and linker executable) environment in baby steps, then I would recommend first simply using Emacs to edit your source, and becoming used to the various shortcut keys and so on. Speaking only about raw editing, I find myself considerably more productive in Emacs than VS given the power of the editing functionality - and less use of the mouse is another upside if you suffer from mouse-related RSI. That's the first baby step you can take.

Unfortunately, the next step - to move from the VS build environment to something cross platform isn't so simple, and I can't see a particularly gradual way to do it. You'll need to decide what your alternative would be - it could be as simple the classic GNU tool chain - make, makedepends, gcc, gdb and related components. Here, I'd recommend Cygwin on Windows - get used to this and you'll be immediately familiar with the tools when you make the jump to a UNIX environment. The details of how to set up a nice environment with this toolchain could probably fill a book or two, but if your needs are simple it is not difficult.

There are certainly other more modern alternatives, although many of them are oriented towards Java - but you can still use things like ANT and Maven with other languages with the appropriate plugin or extension.

Once you've got your non-VS build set up (nothing to do with Emacs), only then can you go about the task of learning how to trigger your builds, fix compile errors and debug your programs using emacs in an integrated way.

See "Emacs For Dev Studio Users".