Increase border and edge with bricks?

Meomye

Hi, my current border is virtually non existent which I would like to remedy but have no idea where to start. It varies in depth and is a long continuous line (no curves) which I would like to even up and (feeling really ambitious) add some sort of bricks so that I can mow over. I would like to know in a simple step by step process if possible, for instance, how do you even plan a neat line? I have seen people put string lines down but how do you know they are straight? Sorry but this has often puzzled me 

Loxley

If you get a couple of bamboo canes and stretch a string tight between them, that should give you a straight line. If the line needs to be parallel to a wall, use a tape measure to check the canes are set at the same distance from the wall. Cut your turf along that line and then set out your bricks along a string line in the same way before you concrete them in. (Set the string low so the bricks touch it). You could also use some long pieces of wood to help you make sure you don't start going wonky (as I did when I attempted this task - see picture!)