Good luck.

I, too, am bad at cleaning. And I end up with a lot of stuff that I don't need, so I guess I'm a hoarder too. Here's what works for me.

For cleaning - Small steps. Do something that only takes a minute - unclutter one table or a half a table. Unload half a dishwasher.
Hire someone if you can afford it. Just enough to take the edge off of the mess. And yes, I de-clutter before my person comes to clean. otherwise the cleaner will never finish. And if there's too much to de-c;utter, I just tell him/her to leave the cluttered room alone, and just clean what's not a difficult chore.
Invite someone over. I have to clean if I have guests.
I'm okay with a little bit of a mess. The trick for me is to never let it get really bad.