Measure the areas that may change
A rough plan is useful even if it is drawn by hand. Mark the house, boundaries, access and any structures or plants you want to retain. Add approximate lengths and widths rather than one overall number for the garden.
The area in square metres helps define the extent of a proposed lawn, surface or planting area. Ground condition affects preparation. Access influences how materials and removed ground can be moved. Those details form part of a per-job landscaping quotation.
If you know about earlier ground work, tell us. Old bases, buried edges and previous alterations can affect the next stage.
Pay attention to the joins
Landscaping details matter where one part meets another. The edge of a lawn needs to suit the adjoining bed or surface. Steps need to work with the levels either side. A path should connect useful points without leaving awkward pieces of ground behind.
We also look at where water currently collects and how proposed changes may influence it. Photograph wet or settled areas when they are visible. Include the surrounding ground so the problem can be understood in context.
Materials can be discussed once the layout and preparation are clearer. It helps to explain the appearance you prefer, but also how you expect to maintain and use the finished area.