It's been 3 long years of confusion and I'm hoping one of you lawn geniuses can give me a timeline. I've done 3 years of my due diligence NOT posting and trying to read and gain my own knowledge, but now, I admit it. I need help.

My lawn is a mess. It probably should be completely ripped up and done over but it's not in the budget. I am patient. We tried to overseed in the fall and its not looking good. I think the birds and animals ran rampant.

Good news- we have a sprinkler.
Bad news- lots of shade in the back, too much sun in some areas in the front. Weeds. Millions of them and every single type you can imagine. Moss EVERYWHERE.

Before you say rip it up and start over, let it be said that I'm not looking for a golf course here. I just need it to be decent!

Timeline:
Now?
Kill moss
Apply preemergent

End of April:
Throw some seed down (why not gamble?)
week later, fertilize
2 weeks later weed killer/control
We aerated the lawn in the fall so I'm guessing we don't need to again?
We dethatched a lot last spring, but the lawn is old so I may need to do more. I'm getting my soil tested, but am guessing it will need lime so where should I throw that in my timeline if it's needed?

Please help. I'm at a loss and I SWEAR I've researched!