I am posting a Design Your Own Garden course here I realise....
This is a checklist I devised to go through with clients who commission a garden design. (Previous posts under Simply Grow on sidebar)
Which of these features would you want or need?
Lawn
Vegetable plot
Patio
Pergola
Raised beds
Pool
Pond
Barbecue
Garden furniture
Ornament/sculpture
Bird bath
Flower borders
Cutting patch
Hedges/fences
Play area
Sand pit
Herb garden
Shed/storage
Greenhouse
Summerhouse
Compost heap
Deck
Washing line
Extra storage for bikes/canoes etc
Other?
You may like to make a garden file with your answers to the questions (there are more to come).
Photographs of your garden as it is now will be helpful...not 'arty' photographs just a warts-and-all record of every part of it.