Methods

Four ways in

Different sites want different tools. Ranked from cheapest to most certain.

The methods

broadcasting   seed by hand or spreader — cheapest
green hay      cut donor meadow hay, scatter fresh
plug plants    pre-grown plugs — instant structure
turf strip     remove the lawn, sow into bare soil

Which one

Broadcasting suits big areas. Plugs suit small gardens and paths. Green hay is the purist's method — it carries the donor meadow's whole seed bank, insects included.