A word about privacy and Windows 10: Refer to Paul Thurrott's excellent how-to article: Windows 10 Tip: Understand and Configure Privacy Settings. He explains in detail what options are available during the upgrade/install and after, and what the settings mean.
There are two methods to upgrade to Windows 10 from your existing install of Windows 7 or 8.1. For this article only high level guidelines are presented. Finer details will vary from system to system, but the below advice should serve to get most people through the process with minimal fuss.
1) An in place upgrade.
2) A clean install.
There are benefits to both, depending on your situation. Let's talk about both scenarios a bit.
In place upgrade to Windows 10 from Windows 7 or 8.1:
You'll get to keep all your existing software installs, with one exception - more on that in a moment. Most of your software will retain it's activation status, although some may need to be re-activated. All your settings will mostly stay intact for those applications. Assuming a healthy base system - no malware infections, adequate disk space, hardware in great condition, decent hardware specifications - this is the easiest path to take. There are however some things you can do to make the upgrade go smoothly.
a) Clean your disk drive. Run the disk cleanup utility in Windows in both user mode and system (admin) mode. Use it to clean out your temp folders, old system restoration points, old windows updates and old service packs, etc.
b) Uninstall all toolbars from all browsers.
c) Update any alternate browsers to the newest version.
d) Run Windows Update and pickup the latest service packs and updates for Microsoft software, especially Office and the OS itself.
e) And the most critical part: Uninstall your Anti-Virus completely, especially if you have Microsoft Security Essentials. Keep your registration information handy for any paid AV product you own, and I recommend downloading the latest version of that AV product to your hard drive before doing the OS upgrade . . . but don't install and activate it until after you have successfully upgraded to Windows 10. If you were using Microsoft Security Essentials then you need to know that there is no version of that for Windows 10 - Microsoft is providing Windows Defender in it's place and it's already included in Win10. You should also be aware that there is a nasty bug (still) where Windows 10 breaks after the upgrade if you left Microsoft Security Essentials installed before the OS upgrade.
f) To upgrade simply accept the prompt you've been ignoring for months. If you blocked the free upgrade follow the reverse steps to unblock it for which ever method you used.
Fresh clean install of Windows 10:
This will be much harder for most people. You will have to re-install all your applications from their source after the OS install. You may have to chase down drivers for your system. You will also have to backup and restore your data. The benefit is you get to start with a clean system. No hangovers from malware or corrupted systems, and no leftover garbage from the original system.
A) You'll need a blank USB thumbdrive with 4GB space or better on hand.
B) Download the free Microsoft Media Creation Tool here.
C) Run that tool - use it to "create installation media for another PC," and tell it to download the appropriate version to match what you have and create an installation USB drive.
D) It will make your USB thumbdrive bootable, and copy the Windows 10 install files to it.
E) Backup everything! And be certain you know how to get your personal/professional data back out of that backup. I recommend you make a second file to file backup to a USB drive (not the one you are using to install Windows 10) of all your photo's, video's, music, documents, financial software databases etc.
F) Determine at least these two hardware components on your system, and download Windows 10 compatible drivers for them in advance to that USB data backup drive:
- Your network adapter, and
- your video card.
- Activating your free upgrade during a clean install: Use your product key from your old Windows 7 or 8.1 installation. Assuming it's legal, and you have not used it already to upgrade to Windows 10 you should be good to go.
- If you already upgraded to Windows 10 in the machine before, you can skip the product key. Activation is tied to your hardware.
H) After the install if you don't have network access then use that driver you downloaded to install the correct files for Windows 10 to talk to the world. Also if your monitor is showing an incorrect resolution - you can now install that video driver if needed. Most of you won't need either.
I) Run Windows update and get fully patched, repeat, reboot, repeat until no updates are available.
J) Install your applications, and update them.
K) Restore your user data to the system.