1. Rescue the Bank of the United States. The failure of this bank in New York had a negative effect at the worst time.
2. Better Federal Reserve appointments. New York Fed should have provided liquidity in 1929 to soften the Crash and limit its fall out. As troubles mounted, the Fed should have cut interest rates.
3. Veto the Smoot Hawley tariffs. Tariffs are taxes, they restrain commerce and production, invite retaliation, and deaden the economy.
4. Be willing to tolerate deficit spending. Spending doesn't stimulate the economy if it is offset by taxes.
5. Institute federal deposit insurance. Probably the single most important policy measure after fiscal and monetary stimulus. It heads off bank runs and permits the financial system to keep functioning. The expansion of deposit insurance to include larger deposits and interbank loans in 2008 is probably the most important factor in the resolution of the crisis.
6. If necessary either get off the gold standard or raise the price of gold. Again, this tends to fend off deflation.
I have read some comments that reflect the Classical school of economics and suggest just letting things work themselves out, arguing that in the long run this is the best solution. Years ago, one writer noted that "people don't eat in the long run." A massive deflationary recession in a modern economy has long lasting negative effects - a rise in suicides, a decline in births and marriages,malnutrition, interrupted education for millions of college and graduate students, the dismantling of the workforce and the decay of capital equipment. and of course, the rise of extremists (Hitler's rise was not caused by hyperinflation - that was long gone by 1933 - it was caused by a wrongheaded austerity program that intensified an already horrible depression).
A deflationary recession is an inexorable decline characterized by financial failure, reduced output, lower prices leading to the postponement of purchases awaiting further price declines, loan defaults due to the increase in the real principal amount owed, failure of financial institutions, layoffs due to the sticky nature of wages and the reluctance to reduce payroll expense by cutting wages and the choice to reduce headcount instead, and political and social instability.