Close Losing Position, Set Trailing Stop to Winning Position

MQL5 - Pair Trading: Close LOSING Position and Set Trailing Stop to WINNING Position Simultaneously

MQL5 - Pair Trading:
When the condition is met,
how do I do this simultaneously?
1) Close the LOSING Position immediately (Position could be a Sell/Buy order of any currency)
2) Set Trailing Stop to WINNING Position immediately (Position could be a Sell/Buy order of another currency)

Hi Johnnybegood
Thanks for your system.
Would you tell us some examples with screen shot for clearly this system ?

Its an idea, I am trying to figure out how to code that....