Throw it on the pile.

A very demoralizing loss at club tonight - my opponent handed me a couple of free pawns and then offered trade after trade. So I thought I was home free! Well, I managed to get down to just pawns and rooks, but then I completely lost the thread. More like I tore my own arm off and clubbed myself with it. 

There must be something to take away from this. I know that trading down was the right idea - but then what? I think my b-pawn was backwards, though I'm still learning about pawns. I guess another missed idea must have been to give the king some breathing room. Around move 24, I realized I didn't really have a plan. What is the most logical way to progress from this point and how do I learn it?