Clarify work with preset files in readme, as I see some confusion in some people's forks.

README.md

@@ -2,17 +2,32 @@
 
 This is a PowerShell script for automation of routine tasks done after fresh installations of Windows 10. This is by no means any complete set of all existing Windows tweaks and neither is it another "antispying" type of script. It's simply a setting which I like to use and which in my opinion make the system less obtrusive.
 
-This repository has been originaly created as complementary to article https://www.dasm.cz/clanek/jak-z-windows-10-udelat-desktopovy-system (written in czech) which explains the respective snippets a bit more in detail. The article was last updated on 2016-08-15 and will not be updated further. All development and discussion has been moved here.
+This repository has been originally created as complementary to article https://www.dasm.cz/clanek/jak-z-windows-10-udelat-desktopovy-system (written in Czech) which explains the respective snippets a bit more in detail. The article was last updated on 2016-08-15 and will not be updated further. All development and discussion has been moved here.
 
 ## Usage
 If you just want to run the script with default preset, simply right click on the *Win10.ps1* file, choose *Run with PowerShell*, and confirm execution policy change. Make sure your account is a member of *Administrators* group as the script attempts to run with elevated privileges.
 
 ### Advanced usage
-The script supports customized presets where you can specify which tweaks should be applied. You can either pass the function names directly as parameters.  
-`powershell.exe -NoProfile -ExecutionPolicy Bypass -File Win10.ps1 EnableFirewall EnableDefender`
+The script consists of separate functions, each of which contains one tweak. The functions can be grouped to *presets*. Preset is simply a list of function names which should be called. If you don't supply any specific preset, the default preset defined by `$preset` array in the beginning of the script will be applied. Any function which is not present or is commented in a preset will not be called, thus the corresponding tweak will not be applied. If you choose to fork the script and adjust the defaults instead of creating a customized preset file, then all you have to modify is the `$preset` array.
 
-Or you can create a file where you write the function names (one function per line) and then pass the filename using *-preset* parameter. Don't forget that the script will try to run with elevated privileges and will use different working directory, therefore use of absolute paths is recommended.  
-`powershell.exe -NoProfile -ExecutionPolicy Bypass -File Win10.ps1 -preset D:\Install\mypreset.txt`
+To supply a customized preset, you can either pass the function names directly as parameters.
+
+    powershell.exe -NoProfile -ExecutionPolicy Bypass -File Win10.ps1 EnableFirewall EnableDefender
+
+Or you can create a file where you write the function names (one function name per line, no commas, whitespaces allowed, comments on separate lines starting with `#`) and then pass the filename using *-preset* parameter. Don't forget that the script will try to run with elevated privileges and will use different working directory, therefore use of absolute paths is recommended.  
+Example of a preset file `mypreset.txt`:
+
+    # Security tweaks
+    EnableFirewall
+    EnableDefender
+
+    # UI tweaks
+    ShowKnownExtensions
+    ShowHiddenFiles
+
+Command using the preset file above:
+
+    powershell.exe -NoProfile -ExecutionPolicy Bypass -File Win10.ps1 -preset D:\Install\mypreset.txt
 
 ## FAQ
 
@@ -38,7 +53,7 @@ Or you can create a file where you write the function names (one function per li
 **A:** Submit a PR or drop me a message. If I find the functionality simple, useful and not dependent on any 3rd party modules or executables, I might add it.
 
 **Q:** Can I use the script or modify it for my / my company's needs?  
-**A:** Sure, knock yourself out. Just don't forget to include copyright notice as per MIT license requirements. I'd also suggest including a link to this github repo as it's very likely that something will be changed, added or improved to keep track with future versions of Windows 10.
+**A:** Sure, knock yourself out. Just don't forget to include copyright notice as per MIT license requirements. I'd also suggest including a link to this GitHub repo as it's very likely that something will be changed, added or improved to keep track with future versions of Windows 10.
 
 **Q:** Why are there repeated pieces of code throughout some functions?  
 **A:** So you can directly take the function block and use it elsewhere, without elaborating on any dependencies.