Strike selection defaults: 0.30 delta for premium-selling strategies (high probability, modest premium), 0.50 delta for ATM directional plays, 0.70+ delta for high-conviction directional bets where you want stock-like exposure with leverage. Reading delta as approximate probability of finishing ITM is the most useful shortcut for beginners — a 0.30 delta short put has roughly a 70% chance of expiring worthless, and that 70% is what makes the strategy work.
Expiration selection: 30–45 DTE is the sweet spot for premium sellers (theta acceleration without gamma danger). 45–60 DTE for premium buyers (more time for thesis to play out). Avoid 0–14 DTE for new traders — gamma swings and pin risk make the math unforgiving. Avoid 90+ DTE for premium sellers — capital efficiency suffers because the daily decay is too slow.