Is your service provider already published to the interfederation eduGAIN by another federation?
We have an opt-out policy regarding eduGAIN for SWAMID Identity Providers, so you should already been able to communicate with most SWAMID member institutions. You may need to talk to the federation that publishes your metadata to eduGAIN about which eduGAIN enabled entity categories to use to get the appropriate attributes released by our IdPs.
If you still want to register your service with SWAMID:
When you got your web service ready with a installed and running Service Provider you need to make it easier for the users to use your service. The hardest step is to make the identity providers to release needed attributes to your service. This can be done in two different ways and you need to do both of them.
Don't forget to enhance user experience with Service Provider Metadata Extensions for Login and Discovery User Interface (MDUI). Look at the example to understand what the MDUI information can do with the user experience. More information and good practice for how to design a good login user interface can be found in the REFEDS login and discovery guidelines.
Example of MDUI use in an Identity Provider. The text (title and description) on the right is provided by Service Provide MDUI elements in SWAMID metadata for the service "Medarbetarportalen".