once tsincrements = // usually 0 – 0.2, effects how quickly the stop will trail
once tsminatrdist = // 0 – 3, but this setting often has no effect at all

once tsatrperiod = // typically 14, how many periods it looks back – not worth optimizing
once tsminstop = // enter the minimum stop distance as set by IG, DJ = 12, NAS = 4, DAX = 5 etc

once tssensitivity = // [0]close;[1]high/low //this chooses how the stop is triggered: 0 = when price closes above/below the trigger level, 1 = previous candle high above trigger or low if short

trailingstoplong = // ts atr distance  // typically 3-10, this is the most important setting
trailingstopshort = // ts atr distance // as above but usually worth optimizing separately

Take note of line 43 if you’re trading Forex (ie use 43 and // line 42)

I think Paul gets the credit for this TS, this is his revised version which will also work with cumulative orders. Note that he advises NOT to use ONCE with tssensitivity

// trailing atr stop incl. cumulative positions
once trailingstoptype2     = 1
if trailingstoptype2 = 1 then
//====================
once tsincrements = tsi // set to 0 to ignore tsincrements
once tsminatrdist = tsm

once tsatrperiod    = 14 // ts atr parameter
once tsminstop      = IG // ts minimum stop distance

tssensitivity = 2 // [1] default [2] high/low [3] low/high [4] typicalprice (not use once)
//====================
if barindex=tradeindex then
trailingstoplong     = tsl // ts atr distance
trailingstopshort    = tss // ts atr distance
else
if longonmarket then
if tsnewsl>0 then
if trailingstoplong>tsminatrdist then
if tsnewsl>tsnewsl[1] then
trailingstoplong=trailingstoplong
else
trailingstoplong=trailingstoplong-tsincrements
endif
else
trailingstoplong=tsminatrdist
endif
endif
endif
if shortonmarket then
if tsnewsl>0 then
if trailingstopshort>tsminatrdist then
if tsnewsl<tsnewsl[1] then
trailingstopshort=trailingstopshort
else
trailingstopshort=trailingstopshort-tsincrements
endif
else
trailingstopshort=tsminatrdist
endif
endif
endif
endif
tsatr=averagetruerange[tsatrperiod]((close/10))/1000
//tsatr=averagetruerange[tsatrperiod]((close/1)) // (forex)
tgl=round(tsatr*trailingstoplong)
tgs=round(tsatr*trailingstopshort)
if not onmarket or ((longonmarket and shortonmarket[1]) or (longonmarket[1] and shortonmarket)) then
tsmaxprice=0
tsminprice=close
tsnewsl=0
mypositionpriceatr = 0
endif
positioncountatr = abs(countofposition)
if tsnewsl > 0 then
if positioncountatr > positioncountatr[1] then
if longonmarket then
tsnewsl = max(tsnewsl,positionprice * tsnewsl / mypositionpriceatr)
else
tsnewsl = min(tsnewsl,positionprice * tsnewsl / mypositionpriceatr)
endif
endif
endif
if tssensitivity=1 then
tssensitivitylong=close
tssensitivityshort=close
elsif tssensitivity=2 then
tssensitivitylong=high
tssensitivityshort=low
elsif tssensitivity=3 then
tssensitivitylong=low
tssensitivityshort=high
elsif tssensitivity=4 then
tssensitivitylong=typicalprice
tssensitivityshort=typicalprice
endif
if longonmarket then
tsmaxprice=max(tsmaxprice,tssensitivitylong)
if tsmaxprice-positionprice>=tgl*pointsize then
if tsmaxprice-positionprice>=tsminstop then
tsnewsl=tsmaxprice-tgl*pointsize
else
tsnewsl=tsmaxprice-tsminstop*pointsize
endif
endif
endif
if shortonmarket then
tsminprice=min(tsminprice,tssensitivityshort)
if positionprice-tsminprice>=tgs*pointsize then
if positionprice-tsminprice>=tsminstop then
tsnewsl=tsminprice+tgs*pointsize
else
tsnewsl=tsminprice+tsminstop*pointsize
endif
endif
endif
if longonmarket then
if tsnewsl>0 then
sell at tsnewsl stop
endif
if tsnewsl>0 then
if low crosses under tsnewsl then
sell at market // when stop is rejected
endif
endif
endif
if shortonmarket then
if tsnewsl>0 then
exitshort at tsnewsl stop
endif
if tsnewsl>0 then
if high crosses over tsnewsl then
exitshort at market // when stop is rejected
endif
endif
endif
mypositionpriceatr = positionprice
endif