Need quick bedspace for your new babies? Here's a surefire way to build them quickly, using nothing but lawn and cardboard.
Groundlevel beds: Cut the lawn/sod about 6-8" deep, in sections you can handle easily. In the space you dug the sod from, lay out sheets of cardboard. Soak the cardboard. Flip the sod chunks upside down, so the grass side is on the cardboard. You now have a new bed, which can be planted into immediately, with a little compost added to the back fill.
Elevated beds: Find a part of the yard that could use a new woodchip path (alongside a bed is a good spot, because it doesn't have to be mowed or edged, because there won't be any grass to grow into your bed). Dig out the same sod chunks outlined above. Lay out the cardboard where you want the new bed, and soak it down. Flip the sod chunks same as above. It's ready to plant. Put down some landscape fabric where you dug out the sod, and cover it with 6-8" of woodchips. You now have a weedfree path that will make compost at it's bottom, which you can harvest every year. Just rake back the top, shovel the bottom into adjacent beds, rake the top back into the bottom, and put a new layer on top.
The primary benefits of instant beds are that you don't need layers of greens and browns like with lasagna beds, and they don't shrink down like lasagna beds.