Enter the total profit or loss for the full year — not individual trades. Find this in your broker's P&L report.
Treated as non-speculative business income. Losses can be carried forward 8 years against business income.
Buying and selling the same stock on the same day. This is speculative income — losses can only be offset against other speculative gains, not against F&O or salary.
Gold, silver, crude oil, etc. on commodity exchanges — treated as non-speculative business income.