1. Download the 'Basic MikTeX' installer from the 'Downloads' page of the MikTeX website:
http://miktex.org/download
When you run this program (which puts enough LaTeX on your hard disc to get you started) accept all the default options except the one that asks "Install missing packages on the fly?" The answer to this is "Yes" the other two options ("No" and "Ask me first") don't seem to work.
After the installation has finished you should be offered the option 'Check For Updates' and you should accept all the updates in this option.
(If 'Check For Updates' option doesn't appear then run MikTeX Console form your start menu and use the 'Check For Updates' option there instead)
2. Download and install TeXstudio:
http://www.texstudio.org/
TeXstudio is a LaTeX centred text editor with a built-in viewer. Accept all the installation defaults.
3. Run TeXstudio from your desktop and select File > New to get an empty document and immediately save it somewhere convenient. Copy/Paste the following code to the file and save it again:
\documentclass{article}
\begin{document}
\title{Hello World}
\maketitle
\section{Introduction}
Then, however, something happened which made every mouth mute and every eye fixed. In the meantime, of course, the rope-dancer had commenced his performance: he had come out at a little door, and was going along the rope which was stretched between two towers, so that it hung above the market-place and the people. When he was just midway across, the little door opened once more, and a gaudily-dressed fellow like a buffoon sprang out, and went rapidly after the first one. ``Go on, halt-foot'' cried his frightful voice, ``go on, lazy-bones, interloper, sallow-face lest I tickle thee with my heel!''
\end{document}
4. Press the F5 key (Compile and view) or click the compile tool on the toolbar. After a second or two you should get a preview of your first LaTeX generated .pdf in the previewer on the right hand side of the screen (by default).