Setting off losses in the unlisted market against gains in the listed market can be done by following these steps:

1. Calculate the total loss from the unlisted market and the total gain from the listed market during the financial year.

2. The loss from the unlisted market can be set off against the gain in the listed market in the same financial year.

3. If the loss from the unlisted market is more than the gain in the listed market, the remaining loss can be carried forward to future years, up to a maximum of eight years.

4. The carried forward loss can be set off only against any future gains in the unlisted market. It cannot be set off against gains in the listed market.

5. To claim the set-off of losses against gains, it is necessary to file the income tax return on or before the due date, and report the losses and gains correctly in the return.

However, it is important to consult with a tax professional for specific guidance on setting off losses against gains, as there may be additional rules and requirements based on the individual’s circumstances and the applicable tax laws.