How Does One Adjust a Carb With a Vacuum Gauge?

Turn the idle screws all the way in and then back them out 1/2 - 1 turn...

Then hook up gauge and warm up the engine... Adjust the idle mixture screws 1/8 - 1/4 turn at a time and to find where you get maximum vacuum and idle speed with tuning tach... Make sure when you finish that both sides are equal turns out...

Here's a good link on diagnosing engine problems with a vacuum gauge....

Vacuum Gauge troubleshooting