Position sizing — how much you put into a single trade — matters more to your long-term results than which assets you pick. Great entries can't save an account that bets too big and blows up on one bad move.
A common rule is to risk a small, fixed fraction of your account on any one idea — often 1–2%. 'Risk' means the distance from your entry to your stop, not the full position size. Set the stop first, then size the position so a loss stays within that limit.
The point is survival. Small, consistent risk lets you be wrong many times and still be in the game when a winning streak arrives. Trade to stay solvent first and profitable second.