I don't undestand how to mine 
Part 1 - Prepare the Client
1. Download the latest client version from here: hxxps://nxtforum.org/nrs-releases/nrs-v1-4-7-1/ (sorry, still can't post links)
2. Unzip the folder
3. You need to download the blockchain.
4. Navigate to "nxt" in your newly unzipp folder
5. Run run.bat (assuming that you have a windows system)
6. After that a new folder called "nxt_db" will appear.
7. If you have already the database somewhere else from a previous version of nxt , close the console window and copy/paste the files inside "nxt_db"
Part 2 - Create an account
If you don't have an account or you want to create a new one just for minting purposes:
1. Run again run.bat
2. Double click "NXT_Wallet" (internet shortcut)
2. Generate a new passphrase
Part 3 - Minting
1. Locate "nxt/conf" folder
2. You will find two files inside
3. Copy paste "nxt-default.properties" inside the folder and rename the new generated file "default.properties"
3. Open "default.properties" using a text editor like sublimetext or notepad++ (you can use notepad also but the result is going to be ugly)
4. Find and change the below parameters (at the end of the file)
nxt.mint.serverAddress=localhost
nxt.mint.currencyCode=ELEMS
nxt.mint.secretPhrase=your passphrase
nxt.mint.unitsPerMint=1
(this means, you will pay 1nxt fee for each ELEMS that you will mint, you can change this accordingly, however greater number increase the difficulty to mint a coin, smaller number decrease the difficulty but you will pay more fees, check "Additional Best practices" below)
nxt.mint.threadPoolSize=1
nxt.mint.initialNonce=0
nxt.mint.isSubmitted=true
5. Save the file
6. Go back in the "nxt" folder and run "mint.bat"
7. A new console window open, if everything is correct after the initialization you will see "Mint worker started"
8. Happy minting
Try and if you need extra help post here. 
The Mint.bat file is not launching for me why?
6. Go back in the "nxt" folder and run "mint.bat"
7. A new console window open, if everything is correct after the initialization you will see "Mint worker started
I have no console window open
First i copied nxt.defaut.properties and paste
Rename the new file default.properties
Open it with Notepad++ delete the text and add this
nxt.mint.serverAddress=localhost
nxt.mint.currencyCode=ELEMS
nxt.mint.secretPhrase=my nxt passphrase
nxt.mint.unitsPerMint=1
nxt.mint.threadPoolSize=1
nxt.mint.initialNonce=0
nxt.mint.isSubmitted=true
Save and launch the Mint.bat nothing happen