Spring seeding

I still need to fill in some bare spots and thicken the lawn in general.  When would the best time be?  I live in St. Louis and I think its zone 6a. 

The best time is right about the first mow.

What about fetilizing, can I do it now to make ure the soil is ready or wait until I seed?

The best time to fertilize is also right about the first mow.  But!  You should not plant seed and fertilize at the same time.  For new seedlings, the best time to fertilize is ....  (wait for it) ....  right about the first mow! 

OK, we've established the time too seed, now I've used a broadcast spreader to drop last falls seed but I'm sure a lot didn't germinate because it wasn't making it to bare earth.  I thought I read about a different kind of seeding tool that puts the seed into the ground.  Have you ever heard of such a device?

Yeah, for farming.  It's called a "no till drill".

If you rough the ground up a bit and then lay down too much seed, then rough it up a bit more, then mist everything at least once a day, you'll be fine. 

Professionals will lay down the seed, put some dirt on top and then run a roller over the top of it to get good soil to seed contact.  Another technique is to rough the dirt up throw down the seed and then rough it up a lot and then do the roller thing. 

The bit of dirt on the seed combined with the roller is a big help, but using too much seed is a big help too. 

Their way will result in a nicer looking lawn right out of the gate.  My way is easier and will even out in a few months.

Please be patient with me, I take everything I see and read literally some times to a fault

paul wheaton wrote:
The best time to fertilize is also right about the first mow. But! You should not plant seed and fertilize at the same time. For new seedlings, the best time to fertilize is .... (wait for it) .... right about the first mow!

This confused me, Planting seed and ferilizing are best done right before the first mow, yet fertilizing and seeding should not be done at the same time?  What if the fertilizer is a feathermeal, I have espoma "turf-tone" 18-0-3.  Is that OK. 

paul wheaton wrote:
If you rough the ground up a bit and then lay down too much seed, then rough it up a bit more, then mist everything at least once a day, you'll be fine.

What is your definition of mist and if you had 10000 sq.ft. how would you mist it?  I know this isn't for the lazy yet, but If I do this right hopefully I won't have to do this much work again.

If you have a bare patch, toss down some seed on the patch before the first mow of all the rest of the grass.  Then toss down some fertilizer on your existing grass, but not on the new seed. 

When the grass in the new patch is mow-worthy, that's the time you can put a little fertilizer on your baby grasses.

Mist:  Just get the soil surface wet, and then a little more.