The first trick is to look at the garage and groan. You've cleaned this thing out numerous times over almost 40 years but as an old fart now you groan and think about giving the job a finger and going back inside to your recliner. Father Knows Best is on you've had the hots for Betty for 60 years. But you made a promise and you're no quitter...
Some hours later with aching legs and a sore back you actually see progress and feel good about the deal.
You learn again quickly that old great stuff you can't live without becomes junk in a hurry and turns into stuff you need to get rid of. You pile it and bag it up.
On another day soon you'll clear out everything else and give the floor a good sweep out and power washing. And then the good warm cat beds and comforters will go down for the feral cats.