5 Trading Rules by Jesse Livermore:
1) Markets are never wrong.
2) Never average losses.
3) Trade only when there’s a clarity of trend.
4) If your position keeps you awake, you are yet to learn position sizing.
5) Trade with a stop loss and know it before entering the trade.
Old school but the evergreen rule:
Book profits periodically and Invest part of profits in buying a hard asset.