Hello, and thanks for your service!

I'm starting a major landscaping project this spring. My goal this year is to create a three new beds for foundation and ornamental plants. I'd like your input on which new bed preparation method is most suitable for proven long term landscape and ornamental plant health and growth. 

I'm not an "good enough" kind of person, but would rather do it right the first time. But neither do I want to invest my time and effort in a way that will not provide any proven long term benefit.  And that is why I'm asking for your expert advice!

I live in a small house built in 1960 on a 1/8 acre suburban lot in Dearborn Heights.  Based on information from neighbors who have lived here much longer than I have, the house has never had major landscaping done, although there was the building contractor installed "row" of arborvitae directly against the front of the house. Those were removed last year. The only other "disturbances" to the soil to my knowledge was the giant lopsided "Y" shaped trenches carved about a foot deep into the ground into which underground 3" PVC pipes were installed to distribute rain water to a pop up head collected from downspouts on either side of the house. 

I'll have to remove the sod in about 50 % of the area I've designated for this years project. Overall, I've a number of the areas to do, ultimately occupying 90% of the entire yard area. I will only work on one area a year, spending the time creating the new beds in the spring/summer and installing the landscape and ornamental plants for those beds in the fall. If that is advised.    

I have a about .5"- 2" of good topsoil under the sod, before I hit the predominate heavy clay soils.  Those souls go down more than 4 feet.

I've put in numerous small veggie gardens in the past, most using the double dig method. 

However, I've been reading recently about less labor intensive "no-dig" and "no till" methods.  However, these articles seem primarily focused on veggie gardens applications.

Are these two methods suitable for foundation and ornamental planting as well?  

If so, which of these two methods works best for my application?  

Given that the "no-dig" and "no-till" methods construct a new "layer" on the top of the existing soil structure, how soon after creating the bed can one plant? 

Since I don't want to raise the overall finished elevation of the existing soil, is it appropriate to remove a 5" to 6" layer to compensate for the height of the added cardboard and compost prior to using one of these two methods? or does that defeat the whole purpose of not disturbing the existing soil structure?

Bottom line, for my application, and desiring optimal long term results, with assurance that my labor is to in vain, would you use double dig, "no-dig" or "no till", or some other method to create these beds?  

Thanks!