For timeframes greater than 5 mins I use a risk manager - which gives precise / exact measures.

I firstly use a support / resistance tool and my eyes to see that there is no / not much in the way between entry and profit - that is a must. Then I use a risk manager to ensure each stop is the same amount .

For example if using a stop of say, $10, each time I ensure the loss is always $10 or less - as I do not want a $20 loss wiping out two profitable 1:1 trades

For timeframes 15min or below I place ALL the support / resistance, pivot lines, etc., on the chart BEFORE I trade so I can easily see the places to enter from and target

Having the s/r lines drawn beforehand is an important key - easy to reject any blocks to a profit - or where to take / consider a strategy for say a 1:1 in a potential 1:3 or 1: many trade. ie where to bail when it all goes against me.

That is when it hits 1:1 - I may consider moving the stop to entry plus commission break-even for some pairs such as EURUSD which whipsaw all the time

risk manager is a must for trade that I have lots of time to place, say 15 mins and above