Couldn't Put It Away

I have to run out for a bit but I wanted to put this up here. This is my second game in months and I'm just getting back into the swing of things but this was easily my win and I blew it. I finished the game in severe time trouble while my opponent had plenty and it really made things difficult for me. How could I have put this guy away? 

I just came home and reviewed this game a bit. I lost the game because I lifted my rook...plain and simple.  If I was able to slide it underneath in my back row and use it to apply pressure to his king the game was a cakewalk. I took 5 pawns worth of material and just shackled it over on my queenside the entire game. 

Nah, you lost because you played the game of trading material for the sake of it.

Can you elaborate on this at all? I was exchanging material - or simplifying - because I was ahead on material. Is this incorrect? 

I know not to trade material when I have a big space advantage but I don't really believe that applied here. 

I'm telling you: It was the rook lift that cost me this game. That said, if there was more time on the clock I would have had this guy easy. 

Incorrect. If you're up material you should be trying to just win. If that means simplifying, fine, but if you have an immediate win, take it.

The rook lift did nothing for your loss, don't blame it. It was an OK choice. After 27...Qb7 you should have thought "what is he threatening? Oh right, mate." and dealt with it. e.g. 28. f3. A one-move oversight.

Also for missed wins (mating attacks) (you should have won on the spot instead of trying to exchange) 18. Bb4+, 19. Bb4+, 21. Qg6 followed by Bb4+, among others. You're ahead by so much with a massive attack on the black king.

Thanks for the feedback and analysis. Bb4+ was an idea I had in my mind, then lost, and then got back too late. Thanks for reminding me.