Hi all
I am looking for NT8 strategy/bot to buy/sell at certain price and do the auto-trailing.
For example: For ES, I plan to sell at 4160 or buy at 4125 with 10 tick auto-trail.
Thank you!

You can use an ATM strategy for that.

https://ninjatrader.com/support/helpGuides/nt8/NT%20HelpGuide%20English.html?advanced_trade_management_atm.htm

But ATM strategy can only apply "either" buy at certain price or sell at certain price, not "both" right?

sevensa 

You can use an ATM strategy for that. https://ninjatrader.com/support/helpGuides/nt8/NT%20HelpGuide%20English.html?advanced_trade_management_atm.htm

I am not really sure I understand what exactly you want. If you know the price you want to sell/buy, why do you need a strategy to do that? Why not just place the orders yourself and then let the ATM handle the trailing stop once filled?

mrdanielkuo 

But ATM strategy can only apply "either" buy at certain price or sell at certain price, not "both" right?

You can do both at the sametime IF you check the OCO feature so that the other order that is still working gets canceled.

Here is an example done with NT7 but you can use it for NT8 just as well:
https://tinytake.s3.amazonaws.com/pulse/paul-ninjatrader/attachments/6617069/TinyTake14-11-2017-09-17-50.mp4