If you are one of the many people who did not get the Windows 10 notification (as I did not), then I will save you a lot of hassle of going through mindless updates and searching the web for what to do (at least that is my intention). Here is what I found:
1) Proceed to this site: https://www.microsoft.com/en-us/software-download/windows10.
2) Follow the download to get the Media Creation Tool for your version of Windows. You will need to know if you are running 32 bit or 64 bit. (Check your System — right click My Computer, select properties.)
3) Download and run the tool. Select whether you want to upgrade now or create installation media. If you want to know how to use the installation media, go here: http://go.microsoft.com/fwlink/p/?LinkId=617364
4) If you upgrade now, be sure to read the requirements here, or you will likely receive errors when attempting to install the upgrade. Also the download will take quite some time depending on your Internet connection.
I have taken you as far as I can. It is now up to you to decide which pill you will take: the red pill or the blue pill.