I have not yet been presented with the update (of course, I'm using the Pro version and have updates paused).
The key thing that was already mentioned was that, if you have any external drives, you should remove them until after the update and then put them back and check your drive letters (D: E: F: G: etc.). Don't forget to reset things back or you may find that data for apps like Outlook, may not work if you have that data stored on drives other than C:
I'd do these steps before the update, if possible:
1) Good time for maintenance. Check how much free space will be available for your install. You'll need at least 64 GB to update the 64-bit OS and ,maybe less for the 32-bit. Just remember that the old windows will stay around for a while unless you do a disk cleanup after the update to remove the old version.
2) If you only have a 32 GB or 64 GB eMMC drive, you may need to offload some files to a jump-drive. At least temporarily.
3) While you are looking at your HDD, try running a CHKDSK on the drive to check for errors. You can also defrag unless you have an SSD and then just run a trim.
4) Go into the Settings app --> "Update & Security". Look for your update history and try to figure out if any older updates failed. Easy to fix but let us know.
5) I would run the Windows Update troubleshooter. You can find it under settings --> "Update & Security" --> Troubleshoot OR you can find it under the Control Panel --> Troubleshooting --> System & Security --> Windows Update. You can also find it on the web. I run it every so often.
6) DISM and SFC: These check your system as far as your Windows Image and your system files. You may want to run this set a couple of times:
Go to command prompt (Admin) by right-clicking the start button then left-clicking on Command Prompt (Admin). I'm running the pro version so the home version may be different. then --
DISM /Online /Cleanup-Image /RestoreHealth
SFC /CHECKNOW
Both take a while
Note: If you are not comfortable with any of these utilities, it is only suggested you preemptively run these. They are good to know about with WIN 10 though.
Suggestions for the Update:
Make sure that, if you have a laptop or tablet, that you plug into power. I've seen these semi-annual updates take overnight. Try not to interfere with the update because you think it is hung due to it taking a LONG time. Especially, if you see a black screen. I've seen the black screen last 1/2 an hour and I've seen it last over an hour. Avoid "killing the update" in the middle. Depending where it is, it could leave you in a bad state. Patience is important.
Ahead of time, especially if you have a laptop, go to the OEM manufacturer like Dell or HP and under support at their website, find and download the drivers for your machine and any external hardware (drives, printers). Also, updating firmware could be a good idea but never kill the power while you do that.
I'm making this sound a lot more difficult than it really is but I wanted to be fairly comprehensive. Remember that the update is the exact same thing as installing a new version of Windows from scratch while trying to keep all of your programs/apps and settings. It takes a while. Not 10 minutes.
After the update is complete, I would go through all of your settings using the settings app and pay special attention to anything you have changed in the past. Just because MS is going to "TRY" to save your setting, changes in code, setting meanings, new settings, etc. these settings may change. If in doubt, leave them alone. Hope this helps. The key we found out after the last update (after they fixed their file losing issue), was Patience and Drivers. MS could have done a better job of communicating with the user that the update is progressing and NEVER show a black screen to you but...