It depends on the pair and my expectations of the trade. I change them often. In mt4 I set for example a 20 pip trailing stop that starts at about -50 pips. The stop won't move until the trade is +20 pips, in which it moves to break even. Once that happens, I usually change the trailing stop to 50 pips so that the price has to move an additional 50 pips to the plus before it will start moving. If volatility is high, i leave it traling 50, as price starts consolidating, I tighten the trailing stop to 20 or 40 and leave it from there. It requires adjustments, however, it is not ideal to leave a 15 or 20 pip trailing stop as it will get hit way too early.
