A trendline pullback usually means that there was a trendline in place, price broke out of this trendline, and you wait for it to pullback to the trendline it has broken from.
I don't use trendlines as a place for entry, so a rough line would do equally well for me. However, unless you have the experience of Flasheart with these to make a judgement on best place, I'd suggest you go with the least subjective way of drawing them. And in that spirit, I'd suggest using the highs and lows rather than drawing it to the opens and closes, which change significantly based on the timeframe you're looking at.