Easiest way to do it is to put layers of wet newspaper then black mulch. I left it for a month and it's as if the weeds were never there. I made holes in the mulch and planted some veges, they are doing great (except for the Shiso which something ate).
You do know you can buy weed barrier fabric and cover the beds. When you plant you put holes in the barrier where your plant goes. Work well for a few people I know and it's similar price to mulching every season.
Mulch worked for me but I am using pots at the moment.
My garden was literally only weeds (our house is my wife's grandparents and the house had sat mainly abandoned for about 3 years when we moved in). After doing the newspaper and mulch technique and leaving it for about 6 weeks the weeds had all decomposed into soil and haven't come back.
The bit that shouldn't surprise me but still does, is the volume change. Add 6 ish cubic metres of mulch and 5 years later is a thin layer of soil comprising maybe 1-2m.
