There are two basic approaches... The one most people do is: they see a shrub or tree they like and buy it. When they get home one says to the other, "Honey, where shall we put the ______?" And the honey says, "Over there would be a good spot." This process repeats itself over and over, until the yard, or parts of it, is bursting with plants. This is an excellent method for those who love foliage because there will be lots of it.

The other method is to not plant ANYTHING (except maybe sod) until a landscape PLAN is created, showing where each plant would be used, and more importantly, how the overall yard is arranged functionally for the needs of the people living there. Some people do not feel confident to make such a plan and hire a professional to do it ... just like they would hire an architect, builder, mechanic, barber, etc. to do those other kinds of things they can't do. They would give some overall direction about their end goals to that person in order that the finished product meets their expectations. Some people do not want to pay the expense of a professional to create a landscape plan and believe that they can do it themselves with a little outside assistance ... such as from an online landscape design forum. This can work out well IF said person has the capability of basic measuring and the ability to draw a rectangle, line and circle. They will also need the ability to wade through information and sort the good from the bad, as in a public forum all manner of advice will come.

As a preliminary task, they'll also need to think through their overall objectives for their property ... not how those objectives will be accomplished (because they might not know that yet) but what effects they want and where they want them. For example, NOT plant a tree or hedge here or there ... but achieve shade, screening, privacy here or there. They will also need to assess their needs for outdoor living and recreational spaces, such as patio, pool, veggie garden, etc., if any of those are desired in the plan

If you have a plot plan that shows your backyard, I'd submit it here, as you'll need some graphic way to communicate what is where. and some graphic way of working out ideas.

(Do you realize that if you had this same property in Hong Kong, you'd likely be a multi-millionaire...?)

I'm editing to add: Getting help here, if expecting to achieve a more or less professional, thought-through type of result, still requires the preparation of a PLAN. Loose ideas that come in pictures or are floating around in waves of thought, do not transform into a good landscape without first assembling into the form of a PLAN.

The blank slate can be super overwhelming! I started with the same thing in my suburban yard and it took a while to work through common mistakes before I finally thought to, y'know, take measurements and draw out a plan, haha.

If you don't feel confident doing it yourself, a landscape designer would definitely be a good idea!

If you're willing to diy, carefully measure the yard dimensions and make yourself a to-scale map of what you currently have, including all existing buildings, garden beds, hard surfaces, etc. I like to use tracing paper over a base paper map to test out different ideas. It doesn't have to be super detailed, and figuring out general ideas/big picture stuff should be done first anyway.

Are you new to gardening?

Thanks for the tips! Yes, brand new to gardening (and homeownership) so just trying to figure out my first steps and how to start :)