start by picking out all of the weeds from the yard by hand trying to remove all of the roots.
till the ground so the soil is loose about 4 to 6 inches deep. I used a pick axe to till.
use a shovel or something to push the dirt around and even out your yard so it isn't all dippy.
go through and pick out any left over roots and rocks from the soil.
spread the seeds over the soil.
walk over the seeds to press them down in to the soil.
water the grass every day to keep consistently moist for the first week.
water every other day, or when the soil begins looking too dry during the second week.
your grass will begin to emerge by the end of week 2. look at it go!
by the end of week 3 it will look a little bit like this.
if it is growing in patchy, don't fret! the grass will eventually spread on its own to fill your entire yard.
it can take months before your yard fills in perfectly. be sure not to walk on it for at least 2 months so the roots can take hold.