What you can and cannot change
On an open trade you can add, move, or remove the stop-loss and take-profit. You cannot change the direction, the entry price, or the size of the original fill — though you can reduce size with a partial close. Modifying a trade is really about managing its exits.
Knowing how to do this cleanly matters, but so does knowing when to leave a trade alone. The mechanics are easy; the discipline is the hard part.
The numbered steps on desktop
Step 1: Open the Terminal (Ctrl+T) and go to the "Trade" tab.
Step 2: Right-click the open position and choose "Modify or Delete Order" — or simply double-click the S/L or T/P value in the row.
Step 3: In the window, type the new Stop Loss and/or Take Profit price. The platform will refuse values that are on the wrong side of the current price or too close to it.
Step 4: Click "Modify" to apply. The stop and target lines on your chart jump to the new levels.
On the chart and on mobile
On the desktop chart you can drag the stop-loss or take-profit line directly to a new price and confirm. On the mobile app, tap the open position, choose to modify it, and enter the new levels. The result is identical.
Whichever route you use, double-check you edited the right line on the right trade, especially with several positions open at once.
An honest risk note
The most damaging modification is widening a stop-loss on a losing trade "to give it room". That is really just choosing to lose more, and it turns small, planned losses into large, unplanned ones. Move stops in your favour or leave them; moving them against yourself is how accounts get wrecked. Set your exits calmly before you enter, and resist editing them in the heat of the moment.