Coat your pea seeds in soil inoculant.
Once your seeds are nicely coated with inoculant, scatter several handfuls over your garden bed. Try to give the seeds enough space (around an inch or so) so they don’t germinate in crowded clumps.
When you’ve got a layer of seeds spread fairly evenly across the surface, use a rake or hand cultivator to work them down into the soil to a depth of about 1/2 to 1 inch.
Water the seeds in thoroughly. If you live in a dry climate that doesn’t get much rain in fall, add a light layer of straw mulch (no more than 1 inch) to help hold in moisture.
Continue harvesting lightly from your pea plants until they begin to flower, at which point the cover crop is at its apex of benefit.