Having trouble with a certain script in batch!

I'm making an application with Batch (I know XD) that backs up a certain file.
I'm stuck where the app does this;
If the directory doesn't exist, make it
If any other files in the first directory exists, delete them
Make a directory in the first directory.

But I can't quite get it right.
Here's What I'm doing:

:setScript1
cls
echo.
echo

---

echo.
echo Minecraft Batch Back-Up - V0.7.4.1 Alpha
echo.
echo

---

echo.
echo.
echo MC Batch Back-Up Is Setting Up The Nessecary Enviroment(s)...

IF not exist dir "C:\%UserName%\Desktop\Minecraft_Back-Ups\" mkdir "C:\%UserName%\Desktop\Minecraft_Back-Ups\"
IF exist dir "C:\%UserName%\Desktop\Minecraft_Back-Ups\*" rmdir "C:\%UserName%\Desktop\Minecraft_Back-Ups\*"
mkdir "C:\%UserName%\Desktop\Minecraft_Back-Ups\%date%_%time%"
pause

Anyone with Batch expertise please help!