Create a listing that supports Christ’s Harbor Church:
In the listing form, click on “Switch to advanced tool.”
Scroll to the Choose a format and price section.
Find the eBay Giving Works section.
If you don't see the eBay Giving Works section on the listing form, click the Add or remove options link in the Choose how you'd like to sell your item section. Select a percentage from the Donation percentage drop-down menu.
Read and accept the terms and conditions.
For more help, please see this eBay help page.