Here's what I see for people (like us) trying to get where we shoot in the 80s most of the time.
First of all, short game. (Ever heard that before?). Specifically, get your putting under control. Then, work on your wedges. If you have three or four high-loft clubs, find out your yardage matrix for the wedges. Work on the quarter and half wedges, and the 3/4 if they work for you. Borrow a copy of Short Game Bible by Dave Pelz, if you can. (Note: most of us mere mortals adopt a little Pelz-Lite rather than his full system/religion). You can really save strokes 30 yds. and in with systematic practice. Don't be afraid to take a short-game lesson if you feel insecure in this area.
I recalibrated my wedges recently - about 6 months after I changes up my wedge mix - and promptly had two of my best rounds of the year.
Second, get your tee shots in the fairway! You don't have to hit your driver 300, you may decide to not use a driver... but, put your tee shots in the fairway, or at least in the first cut of rough. Approach shots hit from the sunshine get closer to the green and flagstick than shots hit from deep in the treeline.
Practice your irons some, but not at the expense of the first two. If you have a smooth swing, the law of averages says you'll hit a few GIR each round it you just get the tee shot near the fairway. If the other shots are a little short or a little long, your newly acquired short-game prowess will get you at least a bogie..
Don't be afraid to warm-up, play nine, and hit a few corrective balls when done. I'm guilty of practicing on the range too much, and not going out for nine more often. The "18 or nothing" mentality doesn't work for those of us with jobs, family, etc. And remember, the USGA let's us add up two nines for an 18-hole score.
The above wisdom should keep you busy for awhile. When you break 90 twice in a row, please send me a $75 lesson fee through PayPal.