I also make an effort to determine which way to press the seams. I do think you get a much better match if they are going in opposite directions, but that's not always possible.
When pinning for sewing, if the seams are both going in the same direction, I flip one, match the seam, pin, then let the seam allowance go back to the way it was pressed. Don't know if my explanation makes sense, but it makes seam matching easier for me.