"Don't put all eggs in one basket" — diversification reduces unsystematic risk. Rule: Min 8-10 mã (đủ diversification), max 25 (không over-diversify). Cross-sector: max 25% portfolio cho 1 ngành. VN example: Banking 25% + Tech 20% + F&B 15% + BĐS 15% + Others 25%.
Rule of 100: % stocks = 100 - age. Age 30 → 70% stocks, 30% bonds. Age 60 → 40% stocks, 60% bonds. Modern view (longer life): Rule of 110. Age 30 → 80% stocks. Aggressive young VN: 90% stocks/crypto + 10% bonds OK.
Annual rebalance: Sau 1 năm portfolio drift (winners grew, losers shrunk). Sell winners, buy losers back to target weight. Effect: Force "buy low, sell high" mechanically. Adds 0.5-1%/năm to long-term return.
Core (70-80%): Stable ETF + blue-chips. Long-term hold. Low maintenance. Satellite (20-30%): Active picks, high-conviction. Higher risk/reward. Example VN: 70% E1VFVN30 ETF + 30% individual top picks (FPT, VCB, MWG).
VN low impact: 0.1% sale tax flat regardless profit. Different from US (cap gains). Tactics: 1) Hold long-term reduces trading cost. 2) Cổ tức cổ phiếu > cash dividend (defer tax). 3) End-of-year planning: defer big sale to next year.
4 regimes: 1) Rising growth + rising inflation → commodities, gold. 2) Rising growth + falling inflation → stocks. 3) Falling growth + rising inflation → inflation-linked bonds. 4) Falling growth + falling inflation → long-term Treasury bonds. Allocation: 30% stocks, 40% long-term bonds, 15% intermediate bonds, 7.5% gold, 7.5% commodities. Sharpe: ~0.7 (better than S&P 500 0.5).
Spreadsheet: Every position: ticker, buy date/price, current value, thesis. Update weekly. Journal: Why bought, when sell, lessons learned. Performance attribution: Quarterly review which positions/sectors driving performance. Tool: Vnstock /app portfolio tracker (free) hoặc Excel custom.
2% max risk per trade. 6% max risk across all open positions. 25% max single position size in portfolio. Adhere — bull market discipline = bear market survival.