This is the hard part, physically anyway. A good rule is to keep your pond shape fairly simple. If you make it too complicated with load of bends and curves, you will waste a heck of a lot of liner. You will see later that you can make the shape interesting with the edging we are going to use. So at this stage decide whether you want a rectanglish shape, a roundish shape, or a squareish shape.
Despite popular belief, size is important! If your pond is too small, it will be difficult to keep the water clear. If it is too large for the garden, it will dominate, rather than blend. Having said that, when you dig the hole it looks enormous, but after you have edged it and filled it with water, it becomes less obtrusive. So a little bit of planning at this point will be good.
A good idea is to get a hosepipe and lay it out where you are planning the pond. Use the hose to give you an outline of the shape. If you do this before you start digging, the final shape and size will be a lot easier to plan. As already stated the final size of the pond will be much smaller than the outline of the hose so don't forget to account for that.
