Alibaba customers generally determine the shipping costs by negotiating with suppliers, so if customers want to change the shipping costs themselves, they can take the following measures:

1. Communicate with suppliers: Customers can contact suppliers directly and explain the reasons and requirements for changing the shipping costs. The two parties can negotiate to reach a common shipping agreement.

2. Discuss the mode of transportation: Customers can discuss different modes of transportation with suppliers to find a more economical and suitable shipping solution. For example, different modes of transportation such as land, sea or air can be used to reduce the shipping costs.

3. Find a suitable transportation company: Customers can find a suitable transportation company on their own to obtain a more competitive shipping quote. When choosing a transportation company, customers need to consider factors such as shipping time, service quality and price.

4. Make reasonable requests: Customers can make some reasonable requests, such as merging orders, optimizing packaging, etc., to reduce logistics costs and freight expenses.

It should be noted that changes in freight rates may affect the supplier's profits and cooperative relationship, so customers should try to reflect the principle of win-win and mutual benefit when negotiating with suppliers.