To explain it simply in the account Dashboard, Delegate Access grants other users access to the My Products tab but not the Account Settings tab. Optionally you can grant individual users purchasing power.
Each user would need their own GoDaddy account (if they already have one or create one for free), then after you send and they accept the invite they can select the account under Delegate Access.
This allows those you select to access and manage the products just as you would, but not be able to see or modify the account profile, billing and payment methods, etc. Obviously you would still only want to grant access to those you trust to manage the products (domains, hosting, website, etc), but there are a few more restrictions like moving a domain out of the account is disabled for example.