Basically, most of what you suggested.
One of the big risks of alcohol consumption is damage to the liver. Thus, if drinking a lot, don't do anything else that damages the liver, like taking medication that can itself lead to liver damage. The most common drug that this includes is acetaminophen (paracetamol).
The next important thing is to get the alcohol to be delivered into the blood (and liver) slowly. That means eating before drinking, drinking slowly, and not taking any medication that worsens the effect of alcohol.
And then comes reducing its effects and speeding up recovery. Drink enough additional fluids (water, juices, etc) before, during and after drinking alcohol. Get enough sleep and give your body time to recover.
With regular alcohol consumption comes vitamin deficiencies. A multivitamin with folate, vitamin B6, thiamine, and vitamin A might help. Iron deficiency and anemia are common, getting enough iron in the diet or through a multivitamin can help with that.
There are lots of things long-term alcohol abuse can cause that can't be treated like this, though. Seizures, nerve damage, pancreatitis, etc.
All in all, I really, really recommend against it, but in this hypothetical scenario, the steps above might reduce the damage done to the body.
How to Protect Your Liver if You Drink Alcohol
Absorption Rate Factors
NHS hangover cures
Mechanisms of vitamin deficiencies in alcoholism
Risks of alcohol misuse
Health Risks of Alcohol