Generally, adding positions during the period of fund decline can reduce costs. Investors can add positions in batches, such as adding positions once when the fund falls 10%, adding positions once when the fund continues to fall to 10%, and so on.

Generally, lightening positions in the process of fund rising can protect capital gains, and lightening positions is also carried out in batches. For example, when the fund's profit reaches 30%, the lightening can be reduced by half first, and then by half when the fund continues to rise, until all the funds are sold.