I suppose in this day and age I should be doing a You Tube video, but I’m too old for that.
Many of us want a reasonably accurate map of our gardens and end up with something that falls short. Here is a fairly simple method which will produce quite an accurate map.
You will need paper, a scale ruler, a garden line and measuring tapes, the longer the better. Draw a pair of lines about 2cm apart down the centre of the paper.
Lay the garden line down along the centre of the longest axis of your garden, tied to canes at each end. Make sure it is straight and taut. Lay a long measuring tape along the line, fixed to one of the canes. You could just lay the tape down if the site is an open one. The canes will be points A and B on your survey.
Work your way along the line, measuring how far from the line all your garden features are at an exact right angle to the line. For each item, you have two measurements; how far along the line and how far from it. Starting from the bottom of the sheet, record both figures, the first in the centre column, the second to whichever side applies.
Leave the two canes in place in case you need to make more measurements.
Choose a suitable scale for drawing up your plan. My A-B axis on the diagram is 7.3m, with perhaps a bit beyond each end. That would fit well enough on an A4 sheet at a scale of 1:50. Draw a line down the centre of your blank sheet, or to one side if the measurements are more on one side. Mark points A and B. Measure and mark in your garden features.
If you are picking up path or border edges then you need measurements every couple of metres, less for straight edges, more for very wavy ones. With care measurements of 5m or more from the base line can be made, provided care is taken to do so at right angles.
For bigger areas use triangles and collect a set of measurements for each line. When drawing up the plan, start by drawing the triangle(s) to scale.
I would then scan my rough plan and using Photoshop Elements, produce a good copy on a fresh layer. One advantage of having the plan on the computer is that it is easily edited if plants or other features are changed.