Check out these websites with great guides for beginners:
http://www.computerhope.com/batch.htm (REAL GOOD)
http://coolhacking-tricks.blogspot.be/2012/01/learn-batch-programming-video-tutorials.html (COMPLICATED)
http://ss64.com/nt/ (SUPERB REFERENCE)
OTHERWISE:
Type the line below in command prompt (cmd) and press enter:
help
This is a list with descriptions of ALL commands in cmd you can use.
If you need more info on a specific command you can type /? at the end of any command and press enter. Here's an example:
color /?
Remember: when writing most commands in a file, keep the entire command on the same line!
@echo off
This first one hides all your commands in the console so that whoever opens your file does not see what codes you have used. Here's a good example of how useful this command is. Save this in a file (filename.bat) and run it:
@echo off
echo hi world
echo watsup? how you doing ? trali dadaaaaaaaa
PAUSE
See? It only displays your text you want to output thanks to @echo off. Now just delete that first line from the file and see how different it runs.
:bla
... some of your code here ...
goto bla
This forms a loop between the pointer (:bla) and the return command (goto bla), which can be used for mischief. Just remember that the pointer could be called anything (eg. :nameitlikeyouwant) and you can have as many as you want in a file but you must use the same name when you return to it using goto command.
start www.google.com
This will start your default web-browser and open the website. This command is usually used to start programs but can equally be used in this manner.